CaWE - now 100% MFC-free

Hello all,

At the end of the last week I actually managed to remove ALL Microsoft MFC bindings from CaWE. :wohow:

It's entirely http://www.wxWidgets.org based now, with only a single source code file left referring to the Win32 API directly. (This is not a problem for porting to Linux, though.)

What remains is
  1. to fix several loose ends that were introduced during the port, i.e. re-add missing features, and fixing bugs, and
  2. to add more Ca3DE-specific features.
CaWE can already deal with the new MatSys, handle Bezier Patches, and load/save cmap files. Terrains support is still missing though.