Editor:
- Use standard button styles for the Quicktags buttons.
- Better style for the TinyMCE buttons (hover/focus/active/disabled).
- Move the fullscreen (DFW) button to the right.
- Better style for the Visual/Text buttons in DFW.
Props avryl, see #27279

git-svn-id: https://develop.svn.wordpress.org/trunk@27857 602fd350-edb4-49c9-b593-d223f7449a82