[Frontend] IN-PROGRESS Refactoring to cleanup SASS file structure

open #95
Moved styles from initialization.scss to user-environ/_layout;
forms.scss, items.scss, tree.scss includes moved into main.scss;

Removed forms.css, items.css, tree.css,
Removed initialization.scss, tree.scss

platform/commonUI/general/res/sass/user-environ/_layout.scss

@@ -216,16 +216,17 @@
 .edit-mode {
     .split-layout {
         .split-pane-component.pane.right {
-            //min-width: 150px;
-            //max-width: 50%;
-            .split-pane-component.pane.bottom {
+            width: 15%;
+            .pane.bottom {
                 min-height: 50px;
-                max-height: 80%;
+                height: 30%;
             }
         }
     }
 }
 
+
+
 .pane {
     position: absolute;
     &.treeview.left {