Remove fa-fw class from all icons

Often it is desirable to NOT have this class applied, and it is easier
to apply its styles if needed rather than un-apply it.

less/forum/Composer.less

@@ -61,6 +61,7 @@
     }
     .icon {
       font-size: 14px;
+      margin-right: 3px;
     }
   }
 }