bugfix: rename fixed_menubar.css.less to fixed_menubar.less

The fixed menubar file is imported in the editing.css.less file and not
used as a stand-alone css file.
bugfix: The google maps widget did not respect a CSS width and height

After removing a redundant DIV layer that held the name of the widget
object class, the CSS for the google maps widget did not get adjusted
appropriately.

fixes #181