Hi,

I'm still going further on wxAui support within wxRuby. 

So here is a patch to add support for the AuiToolBar class and its dependencies:
 - AuiToolBarArt
 - AuiDefaultToolBarArt
 - AuiToolBarEvent
 - AuiToolBarItem

Currently wxWidgets has no docs on these classes while they are supported. So there are also no docs for wxRuby. This
should be added later (maybe after the on-going freshup work done in wxAui).

The C headers already contain the new API that has been commited in wxWidgets trunk, but commented (until wxWidgets
releases the next version and wxRuby be based on it).

Regards,

Pascal