Elastic: Add text aligning for toolbar items

For very short button text e.g. "Add" the text has to be centered.

skins/elastic/styles/widgets/menu.less

@@ -53,6 +53,7 @@
             line-height: 1.5;
             cursor: pointer;
             font-size: 1rem;
+            text-align: center;
 
             &:before {
                 height: 1.75rem !important;
@@ -254,6 +255,7 @@
                 line-height: @listing-line-height;
                 display: block;
                 padding: 0 .5rem;
+                text-align: left;
 
                 &:before {
                     line-height: inherit;