Fix padding issue for dialogs according Material design guide lines

Author: reevolt

less/_dialogs.less

@@ -18,7 +18,7 @@
   // Modal body
   // Where all modal content resides (sibling of .modal-header and .modal-footer)
   .modal-body {
-    padding-top:    0px;
+    padding-top:    24px;
     padding-right:  24px;
     padding-bottom: 16px;
     padding-left:   24px;