[Frontend] Manual re-do of collapse/expand panes

open #90
Major work on new .mini-tab elements, used
as controls to expand/collapse panes;
Cleaned up splitter hover behavior;
Changed mixin controlGrippy to not be tied
to :before;

platform/commonUI/general/res/sass/_global.scss

@@ -34,10 +34,6 @@
 	font-style: normal;
 }
 
-.ui-symbol {
-	font-family: 'symbolsfont';
-}
-
 /************************** HTML ENTITIES */
 a {
 	color: $colorA;