First step at wrapping base elements in gst-python

First step at wrapping base elements in gst-python

Original commit message from CVS:
First step at wrapping base elements in gst-python
* configure.ac:
Commenting out weird debugging statement dating from gst-python's
and which causes problems with gstbasesrc.h anonymous union.
* gst/Makefile.am:
Added base.defs
* gst/base.defs:
New base elements definition files
* gst/gst.defs:
* gst/gst.override:
Add base elements