[GSoC] Merge winecfg and Control Panel

[Vincent Povirk]

You can pretty much ignore everything in the actual C source files of
appwiz.c except the CPlApplet function. CPL_STARTWPARMSW is
unimportant, and all CPL_DBLCLK does is create a window.

The only difference from the layout of a normal Windows program is
that a control panel applet does not include its own message loop. The
caller takes care of that.

See also http://msdn.microsoft.com/en-us/library/bb776392%28VS.85%29.aspx