CSS Improved and Favicons

* The CSS for the theme has been improved in several places to utilize
more CSS gradients and fewer images.  This reduces the amount of
downloads and improves the look and feel on high resolution displays.
* I have make the "EDIT" buttons smaller and less obnoxious for editors
* I have added a new favicon option to the theme.  It won't
automatically change your favicon but you can pick one in the customizer
when you choose between other images for the look and feel.  I have
provided both old and new style UUA favicons.
* The top menu has been adjusted so that it starts further to the right
unless there is not enough room.