Rename JS sub-components so that descriptors are before the noun, not after

To be consistent with the naming in PHP world.

e.g. ReplyComposer instead of ComposerReply

framework/core/less/forum/discussion.less

@@ -329,7 +329,7 @@
 .post-icon {
   float: left;
 }
-.post-activity {
+.event-post {
   &, & a {
     color: @fl-body-muted-color;
   }
@@ -337,11 +337,11 @@
     font-weight: bold;
   }
 }
-.post-activity-info {
+.event-post-info {
   font-size: 15px;
   margin-bottom: 5px;
 }
-.post-discussion-renamed {
+.discussion-renamed-post {
   & .old-title, & .new-title {
     font-weight: normal;
     font-style: italic;
@@ -439,7 +439,7 @@
       }
     }
   }
-  .post-activity {
+  .event-post {
     padding-left: 30px;
   }
   .post-icon {

framework/core/less/forum/user.less

@@ -162,7 +162,7 @@
     }
   }
 }
-.activity-post {
+.post-activity {
   overflow: hidden;
 
   & .title {