xwt.widget subdir

I'm thinking that there might need to be a subdir for xwt.widget.

The thing about xwt.widget is it is the immediate reference for people using
XWT.  Hence, surely, you just want the 'designed for instant usage' widgets
to appear there.  However, to take advantage of the theming model,
xwt.widget also has to contain things designed not to be used unless
you-know-how: tab, focusable, selectable, draggable, splitbar, redirect,
treeleaf, onedimensional, and a few others.

Might it be worth 'hiding' these in a subdir of xwt.widget?  That way they
can still be there and documented for use, but it helps 'ease' in the novice
developer.

xwt.widget.... <- I've no idea what to call it.  Suggestions?