Valo Sass API refactoring (#13668)

Valo Sass API refactoring (#13668)

Also fixes #13672 (added ‘notification’ v-included-components list)

Fixes #13746 as well (DragAndDropWrapper won’t hide the drag source any
more)

Loads of smaller tweaks and fixes, went through almost all components
again and fixed any issues I could find in testing.

Testing done with the following:
Desktop (OS X Mavericks)
-Safari 7
-Chrome 35
-Firefox 24.5
-Opera 21, 12
-Internet Explorer 8,10

Mobile:
-iOS 7
-Android 4
-Android 2.3
-Windows Phone 8

Change-Id: Ide32cacd1958b5b8db85afe23f455ad3140a7d21