Add responsiveness for footer. Update gulpjs, package.json and bootstrap sass

static/assets/bootstrap/sass/_modal.sass

@@ -0,0 +1,175 @@
+// .modal-open      - body class for killing the scroll
+// .modal           - container to scroll within
+// .modal-dialog    - positioning shell for the actual modal
+// .modal-content   - actual modal w/ bg and corners and stuff
+
+// Kill the scroll on the body
+.modal-open
+  overflow: hidden
+
+// Container that the modal scrolls within
+.modal
+  position: fixed
+  top: 0
+  right: 0
+  bottom: 0
+  left: 0
+  z-index: $zindex-modal
+  display: none
+  overflow: hidden
+
+  // Prevent Chrome on Windows from adding a focus outline. For details, see
+  // https://github.com/twbs/bootstrap/pull/10951.
+  outline: 0
+
+  // We deliberately don't use `-webkit-overflow-scrolling: touch;` due to a
+  // gnarly iOS Safari bug: https://bugs.webkit.org/show_bug.cgi?id=158342
+  // See also https://github.com/twbs/bootstrap/issues/17695
+
+  .modal-open &
+    overflow-x: hidden
+    overflow-y: auto
+
+// Shell div to position the modal with bottom padding
+.modal-dialog
+  position: relative
+  width: auto
+  margin: $modal-dialog-margin
+
+  // allow clicks to pass through for custom click handling to close modal
+  pointer-events: none
+
+  // When fading in the modal, animate it to slide down
+  .modal.fade &
+    +transition($modal-transition)
+
+    transform: translate(0, -25%)
+
+  .modal.show &
+    transform: translate(0, 0)
+
+.modal-dialog-centered
+  display: flex
+  align-items: center
+  min-height: calc(100% - (#{$modal-dialog-margin} * 2))
+
+// Actual modal
+.modal-content
+  position: relative
+  display: flex
+  flex-direction: column
+  width: 100%
+
+  // Ensure `.modal-content` extends the full width of the parent `.modal-dialog`
+  // counteract the pointer-events: none; in the .modal-dialog
+  pointer-events: auto
+  background-color: $modal-content-bg
+  background-clip: padding-box
+  border: $modal-content-border-width solid $modal-content-border-color
+
+  +border-radius($modal-content-border-radius)
+  +box-shadow($modal-content-box-shadow-xs)
+
+  // Remove focus outline from opened modal
+  outline: 0
+
+// Modal background
+.modal-backdrop
+  position: fixed
+  top: 0
+  right: 0
+  bottom: 0
+  left: 0
+  z-index: $zindex-modal-backdrop
+  background-color: $modal-backdrop-bg
+
+  // Fade for backdrop
+  &.fade
+    opacity: 0
+
+  &.show
+    opacity: $modal-backdrop-opacity
+
+// Modal header
+// Top section of the modal w/ title and dismiss
+.modal-header
+  display: flex
+  align-items: flex-start
+
+  // so the close btn always stays on the upper right corner
+  justify-content: space-between
+
+  // Put modal header elements (title and dismiss) on opposite ends
+  padding: $modal-header-padding
+  border-bottom: $modal-header-border-width solid $modal-header-border-color
+
+  +border-top-radius($modal-content-border-radius)
+
+  .close
+    padding: $modal-header-padding
+
+    // auto on the left force icon to the right even when there is no .modal-title
+    margin: (-$modal-header-padding) (-$modal-header-padding) (-$modal-header-padding) auto
+
+// Title text within header
+.modal-title
+  margin-bottom: 0
+  line-height: $modal-title-line-height
+
+// Modal body
+// Where all modal content resides (sibling of .modal-header and .modal-footer)
+.modal-body
+  position: relative
+
+  // Enable `flex-grow: 1` so that the body take up as much space as possible
+  // when should there be a fixed height on `.modal-dialog`.
+  flex: 1 1 auto
+  padding: $modal-inner-padding
+
+// Footer (for actions)
+.modal-footer
+  display: flex
+  align-items: center
+
+  // vertically center
+  justify-content: flex-end
+
+  // Right align buttons with flex property because text-align doesn't work on flex items
+  padding: $modal-inner-padding
+  border-top: $modal-footer-border-width solid $modal-footer-border-color
+
+  // Easily place margin between footer elements
+  > :not(:first-child)
+    margin-left: .25rem
+
+  > :not(:last-child)
+    margin-right: .25rem
+
+// Measure scrollbar width for padding body during modal show/hide
+.modal-scrollbar-measure
+  position: absolute
+  top: -9999px
+  width: 50px
+  height: 50px
+  overflow: scroll
+
+// Scale up the modal
++media-breakpoint-up(sm)
+  // Automatically set modal's width for larger viewports
+  .modal-dialog
+    max-width: $modal-md
+    margin: $modal-dialog-margin-y-sm-up auto
+
+  .modal-dialog-centered
+    min-height: calc(100% - (#{$modal-dialog-margin-y-sm-up} * 2))
+
+  .modal-content
+    +box-shadow($modal-content-box-shadow-sm-up)
+
+  .modal-sm
+    max-width: $modal-sm
+
+
++media-breakpoint-up(lg)
+  .modal-lg
+    max-width: $modal-lg