Use sass compiling for bootstrap

Remove static version of bootstrap css
Add bootstrap sources
Add bootswatch sources and variable file
Improve the way admin css is handled
This finishes #162

static_common/common/vendor/bootstrap/scss/bootstrap-grid.scss

+@import "mixins/banner";
+@include bsBanner(Grid);
+
+$include-column-box-sizing: true !default;
+
+@import "functions";
+@import "variables";
+@import "maps";
+
+@import "mixins/lists";
+@import "mixins/breakpoints";
+@import "mixins/container";
+@import "mixins/grid";
+@import "mixins/utilities";
+
+@import "vendor/rfs";
+
+@import "root";
+
+@import "containers";
+@import "grid";
+
+@import "utilities";
+// Only use the utilities we need
+// stylelint-disable-next-line scss/dollar-variable-default
+$utilities: map-get-multiple(
+  $utilities,
+  (
+    "display",
+    "order",
+    "flex",
+    "flex-direction",
+    "flex-grow",
+    "flex-shrink",
+    "flex-wrap",
+    "justify-content",
+    "align-items",
+    "align-content",
+    "align-self",
+    "margin",
+    "margin-x",
+    "margin-y",
+    "margin-top",
+    "margin-end",
+    "margin-bottom",
+    "margin-start",
+    "negative-margin",
+    "negative-margin-x",
+    "negative-margin-y",
+    "negative-margin-top",
+    "negative-margin-end",
+    "negative-margin-bottom",
+    "negative-margin-start",
+    "padding",
+    "padding-x",
+    "padding-y",
+    "padding-top",
+    "padding-end",
+    "padding-bottom",
+    "padding-start",
+  )
+);
+
+@import "utilities/api";

static_common/common/vendor/bootstrap/scss/bootstrap-reboot.scss

+@import "mixins/banner";
+@include bsBanner(Reboot);
+
+@import "functions";
+@import "variables";
+@import "maps";
+@import "mixins";
+@import "root";
+@import "reboot";

static_common/common/vendor/bootstrap/scss/bootstrap-utilities.scss

+@import "mixins/banner";
+@include bsBanner(Utilities);
+
+// Configuration
+@import "functions";
+@import "variables";
+@import "maps";
+@import "mixins";
+@import "utilities";
+
+// Layout & components
+@import "root";
+
+// Helpers
+@import "helpers";
+
+// Utilities
+@import "utilities/api";

static_common/common/vendor/bootstrap/scss/bootstrap.scss

+@import "mixins/banner";
+@include bsBanner("");
+
+
+// scss-docs-start import-stack
+// Configuration
+@import "functions";
+@import "variables";
+@import "maps";
+@import "mixins";
+@import "utilities";
+
+// Layout & components
+@import "root";
+@import "reboot";
+@import "type";
+@import "images";
+@import "containers";
+@import "grid";
+@import "tables";
+@import "forms";
+@import "buttons";
+@import "transitions";
+@import "dropdown";
+@import "button-group";
+@import "nav";
+@import "navbar";
+@import "card";
+@import "accordion";
+@import "breadcrumb";
+@import "pagination";
+@import "badge";
+@import "alert";
+@import "progress";
+@import "list-group";
+@import "close";
+@import "toasts";
+@import "modal";
+@import "tooltip";
+@import "popover";
+@import "carousel";
+@import "spinners";
+@import "offcanvas";
+@import "placeholders";
+
+// Helpers
+@import "helpers";
+
+// Utilities
+@import "utilities/api";
+// scss-docs-end import-stack

static_common/common/vendor/bootstrap/scss/forms/_floating-labels.scss

+.form-floating {
+  position: relative;
+
+  > .form-control,
+  > .form-control-plaintext,
+  > .form-select {
+    height: $form-floating-height;
+    line-height: $form-floating-line-height;
+  }
+
+  > label {
+    position: absolute;
+    top: 0;
+    left: 0;
+    width: 100%;
+    height: 100%; // allow textareas
+    padding: $form-floating-padding-y $form-floating-padding-x;
+    overflow: hidden;
+    text-align: start;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+    pointer-events: none;
+    border: $input-border-width solid transparent; // Required for aligning label's text with the input as it affects inner box model
+    transform-origin: 0 0;
+    @include transition($form-floating-transition);
+  }
+
+  > .form-control,
+  > .form-control-plaintext {
+    padding: $form-floating-padding-y $form-floating-padding-x;
+
+    &::placeholder {
+      color: transparent;
+    }
+
+    &:focus,
+    &:not(:placeholder-shown) {
+      padding-top: $form-floating-input-padding-t;
+      padding-bottom: $form-floating-input-padding-b;
+    }
+    // Duplicated because `:-webkit-autofill` invalidates other selectors when grouped
+    &:-webkit-autofill {
+      padding-top: $form-floating-input-padding-t;
+      padding-bottom: $form-floating-input-padding-b;
+    }
+  }
+
+  > .form-select {
+    padding-top: $form-floating-input-padding-t;
+    padding-bottom: $form-floating-input-padding-b;
+  }
+
+  > .form-control:focus,
+  > .form-control:not(:placeholder-shown),
+  > .form-control-plaintext,
+  > .form-select {
+    ~ label {
+      opacity: $form-floating-label-opacity;
+      transform: $form-floating-label-transform;
+    }
+  }
+  // Duplicated because `:-webkit-autofill` invalidates other selectors when grouped
+  > .form-control:-webkit-autofill {
+    ~ label {
+      opacity: $form-floating-label-opacity;
+      transform: $form-floating-label-transform;
+    }
+  }
+
+  > .form-control-plaintext {
+    ~ label {
+      border-width: $input-border-width 0; // Required to properly position label text - as explained above
+    }
+  }
+}

static_common/common/vendor/bootstrap/scss/forms/_form-range.scss

+// Range
+//
+// Style range inputs the same across browsers. Vendor-specific rules for pseudo
+// elements cannot be mixed. As such, there are no shared styles for focus or
+// active states on prefixed selectors.
+
+.form-range {
+  width: 100%;
+  height: add($form-range-thumb-height, $form-range-thumb-focus-box-shadow-width * 2);
+  padding: 0; // Need to reset padding
+  background-color: transparent;
+  appearance: none;
+
+  &:focus {
+    outline: 0;
+
+    // Pseudo-elements must be split across multiple rulesets to have an effect.
+    // No box-shadow() mixin for focus accessibility.
+    &::-webkit-slider-thumb { box-shadow: $form-range-thumb-focus-box-shadow; }
+    &::-moz-range-thumb     { box-shadow: $form-range-thumb-focus-box-shadow; }
+  }
+
+  &::-moz-focus-outer {
+    border: 0;
+  }
+
+  &::-webkit-slider-thumb {
+    width: $form-range-thumb-width;
+    height: $form-range-thumb-height;
+    margin-top: ($form-range-track-height - $form-range-thumb-height) * .5; // Webkit specific
+    @include gradient-bg($form-range-thumb-bg);
+    border: $form-range-thumb-border;
+    @include border-radius($form-range-thumb-border-radius);
+    @include box-shadow($form-range-thumb-box-shadow);
+    @include transition($form-range-thumb-transition);
+    appearance: none;
+
+    &:active {
+      @include gradient-bg($form-range-thumb-active-bg);
+    }
+  }
+
+  &::-webkit-slider-runnable-track {
+    width: $form-range-track-width;
+    height: $form-range-track-height;
+    color: transparent; // Why?
+    cursor: $form-range-track-cursor;
+    background-color: $form-range-track-bg;
+    border-color: transparent;
+    @include border-radius($form-range-track-border-radius);
+    @include box-shadow($form-range-track-box-shadow);
+  }
+
+  &::-moz-range-thumb {
+    width: $form-range-thumb-width;
+    height: $form-range-thumb-height;
+    @include gradient-bg($form-range-thumb-bg);
+    border: $form-range-thumb-border;
+    @include border-radius($form-range-thumb-border-radius);
+    @include box-shadow($form-range-thumb-box-shadow);
+    @include transition($form-range-thumb-transition);
+    appearance: none;
+
+    &:active {
+      @include gradient-bg($form-range-thumb-active-bg);
+    }
+  }
+
+  &::-moz-range-track {
+    width: $form-range-track-width;
+    height: $form-range-track-height;
+    color: transparent;
+    cursor: $form-range-track-cursor;
+    background-color: $form-range-track-bg;
+    border-color: transparent; // Firefox specific?
+    @include border-radius($form-range-track-border-radius);
+    @include box-shadow($form-range-track-box-shadow);
+  }
+
+  &:disabled {
+    pointer-events: none;
+
+    &::-webkit-slider-thumb {
+      background-color: $form-range-thumb-disabled-bg;
+    }
+
+    &::-moz-range-thumb {
+      background-color: $form-range-thumb-disabled-bg;
+    }
+  }
+}

static_common/common/vendor/bootstrap/scss/forms/_form-text.scss

+//
+// Form text
+//
+
+.form-text {
+  margin-top: $form-text-margin-top;
+  @include font-size($form-text-font-size);
+  font-style: $form-text-font-style;
+  font-weight: $form-text-font-weight;
+  color: $form-text-color;
+}