docs/libs/gstreamer-libs-sections.txt: Added new symbol to docs.

docs/libs/gstreamer-libs-sections.txt: Added new symbol to docs.

Original commit message from CVS:
* docs/libs/gstreamer-libs-sections.txt:
Added new symbol to docs.

* libs/gst/base/gstbasesrc.c: (gst_base_src_class_init),
(gst_base_src_init), (gst_base_src_set_format),
(gst_base_src_default_query), (gst_base_src_query),
(gst_base_src_default_do_seek), (gst_base_src_do_seek),
(gst_base_src_perform_seek), (gst_base_src_send_event),
(gst_base_src_default_event), (gst_base_src_event_handler),
(gst_base_src_set_property), (gst_base_src_get_property),
(gst_base_src_wait), (gst_base_src_do_sync),
(gst_base_src_update_length), (gst_base_src_get_range),
(gst_base_src_check_get_range), (gst_base_src_loop),
(gst_base_src_default_negotiate), (gst_base_src_start),
(gst_base_src_activate_push), (gst_base_src_activate_pull),
(gst_base_src_change_state):
* libs/gst/base/gstbasesrc.h:
Implement seeking to other formats than _BYTES.
Implement more seeking methods correctly.
Doc updates.
Added query vmethod.
Added do_seek vmethod to make life easier for subclasses
when seeking.
API addition: gst_base_src_set_format()