This reverts commit a12d7458.

Conflicts:

	atspi/atspi-constants.h

Reverting these enum clean-ups for now, since they require pygobject 2.28.0
for pyatspi, at least one user is pulling git while using pygobject 2.26.0,
upgrading pygobject is likely to be a complicated process that may break
things, and these changes are only code clean-ups that will not really benefit
users.  Will reinstate in a separate branch and merge some time in the future.