BISERVER-9050 - Icons in the UI should be displayed based in theme selected.

Moved PUC icons out of user-console and into the common themes in gwt-widgets. then modified how they are referenced in PUC to use styles from globalOnyx/globalSlate/globalXXX css files to drive the background image... making them "themeable".

Updated the import dialog to use the common BusyIndicator.
Merge pull request #455 from rfellows/dev

BISERVER-9050 - Icons in the UI should be displayed based in theme selected