[gef-dev] Changes to EditPartViewers

[Randy Hudson <hudsonr@xxxxxxxxxx>]

We intend to remove the method:
        public
void dispose();
from EditPartViewer.  This means
you no longer have to call dispose on the viewer, you only have to dispose
its Control.  In fact, having this method was confusing because it
wasn't clear if you needed to call the method AND dispose the control manually.

This change is consistent with the way
JFace Viewers work.  implementations of EditPartViewer can override
handleDispose(), which is called from a dispose listener on the control.

-Randy