added miissing classes and symbols (123 more to go) removed removed symbols from section file fixed many doc-comments

Original commit message from CVS:
* docs/gst/gstreamer-docs.sgml:
* docs/gst/gstreamer-sections.txt:
* docs/gst/tmpl/.cvsignore:
* gst/gstbin.c:
* gst/gstiterator.c:
* gst/gstutils.c:
* gst/registries/gstxmlregistry.h:
added miissing classes and symbols (123 more to go)
removed removed symbols from section file
fixed many doc-comments