Fix appearance of markedit toolbar

* Regen jquery-ui css with our colors
* Change setting so toolbar uses icons for a dark background
* Add padding to edit textarea to make it the same width as
  the toolbar.
setting resize of markedit textareas to none
more tweaks to make the markedit preview pane and toolbar homogenous with the site CSS
unwinding my changes, as they seem to have cascading negative affect
Merge pull request #93 from caktus/markedit-toolbar

Fix appearance of Markedit toolbar