Adjustment proposal - DWM support for for Color Setting (CCHROME)

... gcconfig.pri.in + src,pro -> same logic as for other additional libs + setting the variable GC_HAVE_DWM.
... Colors.CPP -> changed location to get the DWM color to use in "menuBar" of MainWindow
    + add comments of what is still not working (don't want to mess up something)

(cherry picked from commit 6f39fc9d305098177ead42c331a55ea85a68270f)