gst-libs/gst/: Generate enum type code with glib-mkenums.

gst-libs/gst/: Generate enum type code with glib-mkenums.

Original commit message from CVS:
* gst-libs/gst/colorbalance/Makefile.am:
* gst-libs/gst/colorbalance/colorbalance.h:
* gst-libs/gst/mixer/Makefile.am:
* gst-libs/gst/mixer/mixer.h:
* gst-libs/gst/play/Makefile.am:
* gst-libs/gst/play/play.h:
* gst-libs/gst/tuner/Makefile.am:
* gst-libs/gst/tuner/tuner.h:
Generate enum type code with glib-mkenums.
* gst-libs/gst/colorbalance/.cvsignore:
* gst-libs/gst/mixer/.cvsignore:
* gst-libs/gst/play/.cvsignore:
* gst-libs/gst/tuner/.cvsignore:
Ignore generated files.