Original commit message from CVS:
* docs/gst/gstreamer-sections.txt:
Reworked query docs.

* gst/gstquery.c: (gst_query_new_formats),
(gst_query_list_add_format), (gst_query_set_formats),
(gst_query_set_formatsv), (gst_query_parse_formats_length),
(gst_query_parse_formats_nth):
* gst/gstquery.h:
Flesh out formats query, added some new methods.
Fix part of #324398.

* tests/check/gst/gstquery.c: (GST_START_TEST), (gstquery_suite):
Added query creation tests.