clipboard-action: make the icon provide feedback when clicked.

rhodecode/public/css/main.less

@@ -100,6 +100,10 b' input + .action-link, .action-link.first'
 	color: @grey4;
 }
 
+.clipboard-action {
+  cursor: pointer;
+}
+
 ul.simple-list{
 	list-style: none;
 	margin: 0;

rhodecode/public/js/src/rhodecode.js

@@ -219,6 +219,10 b' var clipboardActivate = function() {'
     var clipboard = new Clipboard('.clipboard-action');
 
     clipboard.on('success', function(e) {
+        var callback = function () {
+            $(e.trigger).animate({'opacity': 1.00}, 200)
+        };
+        $(e.trigger).animate({'opacity': 0.15}, 200, callback);
         e.clearSelection();
     });
 };