Fix for gmerlin-0.1.6pre2 (Gdk-ERROR)

If you get errors like:

Gdk-ERROR **: BadWindow (invalid Window parameter)
serial 369 error_code 3 request_code 128 minor_code 2
Gdk-ERROR **: BadWindow (invalid Window parameter)
serial 370 error_code 3 request_code 128 minor_code 2

you can open the file src/playlistwidget.cc and delete the lines 843 and 844. This should help.