Upgrading Font Awesome vendor files from 3.2.1 to 4.2.0

* updating vendor files
* updating class syntax (to new FA-based classes) for all UI elements
* correcting broken tests

lms/static/sass/course/wiki/_wiki.scss

@@ -278,30 +278,6 @@ section.wiki {
           color: $link-color;
           font-weight: bold;
           background-color: $gray-l4;
-
-          .icon-view,
-          .icon-home {
-            background-position: -25px 0;
-          }
-
-          .icon-edit {
-            background-position: -25px -25px;
-          }
-
-          .icon-changes,
-          .icon-time {
-            background-position: -25px -49px;
-          }
-
-          .icon-attachments,
-          .icon-file {
-            background-position: -25px -73px;
-          }
-
-          .icon-settings {
-            background-position: -25px -99px;
-          }
-
         }
       }
     }
@@ -318,38 +294,14 @@ section.wiki {
         float: left;
         display: block;
         width: 25px;
-        height: 25px;
         margin-right: 3px;
-        background: url(../images/wiki-icons.png) no-repeat;
+        margin-top: 5px;
       }
 
       [class^="icon-"] {
         padding-right: ($baseline/4);
       }
 
-      .icon-view,
-      .icon-home {
-        background-position: 0 0;
-      }
-
-      .icon-edit {
-        background-position: 0 -25px;
-      }
-
-      .icon-changes,
-      .icon-time {
-        background-position: 0 -49px;
-      }
-
-      .icon-attachments,
-      .icon-file {
-        background-position: 0 -73px;
-      }
-
-      .icon-settings {
-        background-position: 0 -99px;
-      }
-
       &:hover, &:focus {
         background-color: $gray-l6;
         text-decoration: none;

lms/static/sass/discussion/_discussion.scss

@@ -11,7 +11,6 @@ body.discussion {
     }
 
     .new-post-icon {
-      margin-top: 8px;
       @include margin-right(7px);
       font-size: 16px;
       vertical-align: middle;

lms/static/sass/discussion/elements/_navigation.scss

@@ -213,7 +213,7 @@
     color: $gray-l2;
   }
 
-  .icon-ok {
+  .icon-check {
     color: $forum-color-marked-answer;
   }