[wxVTK] Bug in class declaration leads to Win32 timer creation failure

[Kenneth P. <sh...@se...>]

See this bug:

<https://sourceforge.net/tracker/?func=detail&aid=1704344&group_id=114757&atid=669338>

The problem is that under Win32, the interactor class is derived from a 
stub base class, not the Win32 subclass that provides a timer 
implementation. I suspect I'll see a similar problem when I build for 
Linux, as it probably should be based on the X subclass.

I'm working on a patch. With the correct interactor base class, I'm now 
seeing a wx warning that wxMouseCaptureLostEvent is not being handled.