(less) Merge pull request twbs#11326 from ZDroid/animations

Add `.animation-*()` mixins

mixins.less

@@ -202,6 +202,30 @@
   -webkit-animation: @animation;
           animation: @animation;
 }
+.animation-name(@name) {
+  -webkit-animation-name: @name;
+          animation-name: @name;
+}
+.animation-duration(@duration) {
+  -webkit-animation-duration: @duration;
+          animation-duration: @duration;
+}
+.animation-timing-function(@timing-function) {
+  -webkit-animation-timing-function: @timing-function;
+          animation-timing-function: @timing-function;
+}
+.animation-delay(@delay) {
+  -webkit-animation-delay: @delay;
+          animation-delay: @delay;
+}
+.animation-iteration-count(@iteration-count) {
+  -webkit-animation-iteration-count: @iteration-count;
+          animation-iteration-count: @iteration-count;
+}
+.animation-direction(@direction) {
+  -webkit-animation-direction: @direction;
+          animation-direction: @direction;
+}
 
 // Backface visibility
 // Prevent browsers from flickering when using CSS 3D transforms.