(js) Replace vs-repeat by md-virtual-repeat

There're some issues with mdVirtualRepeat that required some changes to
our app:

1. Having multiple directives with md-virtual-repeat doesn't work well.
That why I added a dedicated div for the md-virtual-repeat directive.
2. ui-sref-active doesn't work well for child nodes of the
md-virtual-repeat element. The class was applied repetitively to a
visible child. I now save which message or card is selected and use the
ng-class directive to highlight the selected list item.

UI/WebServerResources/bower.json

@@ -8,7 +8,6 @@
     "angular-ui-router": "latest",
     "ui-router-extras": "latest",
     "angular-recursion": "latest",
-    "angular-vs-repeat": "latest",
     "angular-file-upload": "latest",
     "angular-material": "master",
     "compass-mixins": "latest",