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

static/assets/bootstrap/sass/_tooltip.sass

@@ -0,0 +1,102 @@
+// Base class
+.tooltip
+  position: absolute
+  z-index: $zindex-tooltip
+  display: block
+  margin: $tooltip-margin
+
+  // Our parent element can be arbitrary since tooltips are by default inserted as a sibling of their target element.
+  // So reset our font and text properties to avoid inheriting weird values.
+  +reset-text
+
+  font-size: $tooltip-font-size
+
+  // Allow breaking very long words so they don't overflow the tooltip's bounds
+  word-wrap: break-word
+  opacity: 0
+
+  &.show
+    opacity: $tooltip-opacity
+
+  .arrow
+    position: absolute
+    display: block
+    width: $tooltip-arrow-width
+    height: $tooltip-arrow-height
+
+    &::before
+      position: absolute
+      content: ""
+      border-color: transparent
+      border-style: solid
+
+.bs-tooltip-top
+  padding: $tooltip-arrow-height 0
+
+  .arrow
+    bottom: 0
+
+    &::before
+      top: 0
+      border-width: $tooltip-arrow-height ($tooltip-arrow-width / 2) 0
+      border-top-color: $tooltip-arrow-color
+
+.bs-tooltip-right
+  padding: 0 $tooltip-arrow-height
+
+  .arrow
+    left: 0
+    width: $tooltip-arrow-height
+    height: $tooltip-arrow-width
+
+    &::before
+      right: 0
+      border-width: ($tooltip-arrow-width / 2) $tooltip-arrow-height ($tooltip-arrow-width / 2) 0
+      border-right-color: $tooltip-arrow-color
+
+.bs-tooltip-bottom
+  padding: $tooltip-arrow-height 0
+
+  .arrow
+    top: 0
+
+    &::before
+      bottom: 0
+      border-width: 0 ($tooltip-arrow-width / 2) $tooltip-arrow-height
+      border-bottom-color: $tooltip-arrow-color
+
+.bs-tooltip-left
+  padding: 0 $tooltip-arrow-height
+
+  .arrow
+    right: 0
+    width: $tooltip-arrow-height
+    height: $tooltip-arrow-width
+
+    &::before
+      left: 0
+      border-width: ($tooltip-arrow-width / 2) 0 ($tooltip-arrow-width / 2) $tooltip-arrow-height
+      border-left-color: $tooltip-arrow-color
+
+.bs-tooltip-auto
+  &[x-placement^="top"]
+    @extend .bs-tooltip-top
+
+  &[x-placement^="right"]
+    @extend .bs-tooltip-right
+
+  &[x-placement^="bottom"]
+    @extend .bs-tooltip-bottom
+
+  &[x-placement^="left"]
+    @extend .bs-tooltip-left
+
+// Wrapper for the tooltip content
+.tooltip-inner
+  max-width: $tooltip-max-width
+  padding: $tooltip-padding-y $tooltip-padding-x
+  color: $tooltip-color
+  text-align: center
+  background-color: $tooltip-bg
+
+  +border-radius($tooltip-border-radius)