(svn r8801) [cpp_gui] -Codechange: few changes towards OO GUI:
-Window related AllocateXxx() functions turned into Window methods
-current Widget renamed to OldWidget
-Widget base class added (still not used)
-CompositeWidget added (also not used)
-Widget rectangle/point handling moved to new file: misc/rect.hpp
-18 new .cpp files added in new dir for several widget types (most of them not used yet)