[Frontend] Create menu style normalized

WTD-1392
WTD-1367
WTD-1391
Some significant reorging in _menus.scss and _constants;
Create menu normalized with context menu styles;
Bottom bar of overlay overflow set to visible to prevent button clipping;

platform/commonUI/general/res/css/items.css

@@ -40,6 +40,14 @@
  * this source code distribution or the Licensing information page available
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  *****************************************************************************/
+/************************** FEATURES */
+/************************** VERY INFLUENTIAL GLOBAL DIMENSIONS */
+/************************** COLORS AND SHADING */
+/************************** RATIOS */
+/************************** LAYOUT */
+/************************** CONTROLS */
+/************************** PATHS */
+/************************** TIMINGS */
 /*****************************************************************************
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