[Frontend] Sanding/positioning and Cancel button added to Messasges dialog

open #159
open #170
Added Cancel button to Messages dialog in DialogService.js;
Important tweaks to layout of messages to allow
bottom-bar to align to bottom in singleton dialog view;
Revised status colors in theme's constants files;

platform/commonUI/dialog/res/templates/overlay.html

@@ -22,8 +22,7 @@
 <div class="abs overlay">
     <div class="abs blocker"></div>
     <div class="abs holder">
-        <a href=""
-           ng-click="ngModel.cancel()"
+        <a ng-click="ngModel.cancel()"
            ng-if="ngModel.cancel"
            class="clk-icon icon ui-symbol close">x</a>
         <div class="abs contents" ng-transclude></div>