parse: fix segfaulting prototype-mismatch

Now YYDEBUG is always set, so check it's value

https://bugzilla.gnome.org/show_bug.cgi?id=712679
Revert "ghostpad: copy sticky events to SRC ghostpads"

This reverts commit 8162a583a4dd68582bf186e2e47a8f0d68fa1980.

Automatically copying the sticky events makes it impossible for apps
and elements to filter the events with event probes. This causes
regressions (See #719437). The best option is to let the app/element
copy and filter the events themselves after the ghostpad target is
set.
inputselector: handle gap events

Use gap events to advance the selector's pad position.

This is relevant to keep sync_streams mode working when one of the
streams doesn't have data all the time.
gstpad: drop assertion on gst_pad_peer_query_position

It is a 'both' query, so it can be sent both ways
parse: Manually insert priv_gst_parse_yyget/set_column prototypes for older flex

Older versions of flex (before 2.5.36) don't add the prototype, so it must
be added manually. We can't check by the version number, because Debian/Ubuntu
patched it into their 2.5.35 at some point.
docs: cosmetic changes in references/decriptions

 * fix typo GstBufferFlag -> GstBufferFlags
 * fix typo GstFeatures -> GstCapsFeatures
 * fix typo GstAllocatorParams -> GstAllocationParams
 * fix typo GstContrlSources -> GstControlSource
 * do not refer to gstcheck as an object
 * make references gtk_init() and tcase_set_timeout() not be references
 * gst_element_get_pad() renamed gst_element_get_static_pad()
 * gst_clock_id_wait_async_full() renamed gst_clock_id_wait_async()
 * _drop_element() is really gst_queue_array_drop_element()
 * gst_pad_accept_caps() was removed, do not refer to it
 * separate GST_META_TAG_MEMORY_STR declaration from description
 * do not describe removed gst_collect_pads_collect()
 * correctly link to GstElementClass' virtual set_context()

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=719614
docs: add missing docs, fixing doc errors

 * add many missing declarations to sections
 * GstController has been removed, update docs
 * skip GstIndex when generating documentation
 * rephrase so gtkdoc doesn't imagine return value
 * add missing argument description for gst_context_new()
 * document GstOutputSelectorPadNegotiationMode and move to header-file

https://bugzilla.gnome.org/show_bug.cgi?id=719614
multiqueue: Wake up on reconfigure event

After patch bda406c4, the state of the singlequeue was set to OK, but nothing
would then wake up the thread, as the other wakeup functions only look at
singlequeues that are marked as having received as not-linked.

https://bugzilla.gnome.org/show_bug.cgi?id=708200
pad: add ACCEPT_INTERCEPT flag

Make a new flag on the pad that tweaks the default behaviour of the
accept-caps function. By default it will check for a subset of the
query-caps result but this is not always desirable. The query-caps
result contains all the constraints to make a good caps decision
upstream but sometimes, like for parsers, not all the constrained caps
fields are known upstream and then a subset check would fail. Switching
to an intersection makes this work again.

See https://bugzilla.gnome.org/show_bug.cgi?id=705024
    https://bugzilla.gnome.org/show_bug.cgi?id=677401
docs: add missing files for distribution

 * add some documentation files in docs/design
 * add docs/list-ulink.xsl so check in docs/manual works

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=719814
info: Protect __categories list in get_category with lock too
info: Make sure the same category is not added twice
tools: gst-launch: don't try to remove already-removed GSource from main loop

It's considered a programming error in recent GLib versions now.
We may already have removed the source by returning FALSE from
the callback if it was fired. Fixes warning with newer GLibs
when interrupting a pipeline with Control-C.
basesrc: Set format to TIME if do-timestamp is TRUE

https://bugzilla.gnome.org/show_bug.cgi?id=702842
docs: clarify encoding of strings in GstStructures and taglists

https://bugzilla.gnome.org/show_bug.cgi?id=709262
Fix some typos in code comments and debug messages

https://bugzilla.gnome.org/show_bug.cgi?id=720029
docs: Fix typos in function/object descriptions

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=720029
info: return existing category if a debug category is registered twice

If a category with the same name is found when creating a new
one, the found category is returned instead of an invalid pointer.
Fixes issue with gst-vaapi (which uses an internal copy of the
codec parsers) caused by commit ccba9130.

https://bugzilla.gnome.org/show_bug.cgi?id=720036
tests: add unit test for registering the same category twice