Additional GdkDebugFlags?

[Tor Lillqvist <tml iki fi>]

Would it be OK to add more values to the GdkDebugFlag enum in
gdkinternals.h in HEAD? (And add corresponding gdk_debug_keys table
entries in gdk.c.) This isn't an API change IMHO...

I have the following in mind, which I have used in the
gtk-1-3-win32-production branch during a recent hacking spree to be
able to pinpoint what debugging output I want more closely:

GDK_DEBUG_COLORMAP, GDK_DEBUG_GDKRGB, GDK_DEBUG_GC, GDK_DEBUG_PIXMAP,
GDK_DEBUG_IMAGE, GDK_DEBUG_INPUT, GDK_DEBUG_CURSOR.

--tml