Following the theory that something lame is better than nothing at all, provide a...

Following the theory that something lame is better than nothing at all, provide a very generic implementation of the ctor wxRegion::wxRegion(size_t n, const wxPoint *points, wxPolygonFillMode fillStyle) by drawing the polygon into a bitmap and using that to create the region.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70537 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775