Improve the description of the latency-time and buffer-time properties in the
audio sink and source.

Expect a GstFlowReturn from the signal handler, just like from the callback.
Also use the return value.

https://bugzilla.gnome.org/show_bug.cgi?id=683865

Drain out the decoder when encountering a gap. Needed for DVD 'still'
sequences which consist of a single video frame, and a large gap
while audio plays.

Still frame events are not OOB downstream. Also, always send
immediately downstream.

Fix up all invocations.

Rename gst_collect_pads_add_pad_full() to gst_collect_pads_add_pad() and fix all
invocations.

Add support for I422_10

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=683838

Fix reading of tags for the case filsrc ! footagdemux ! fooparse ! ..
where we would not read the tags because we never start our own
streaming thread.

https://bugzilla.gnome.org/show_bug.cgi?id=673185

streams with non-TIME segments will not have timestamps ...
... and therefore will never unblock the other streams.

Fixes blocking issue when using playbin suburi feature

Don't align the palette data. Fixes endless loop when trying to align
paletted formats.

Only make the navigation event writable when we need to change it.

It needs to be reworked for 1.0

When we are operating in pull mode, we need to pull from upstream and push
downstream. Also make sure to push tags first.

... and clean up some related resolved FIXMEs

Only provide a clock when we are not flushing, this means that we have posted a
PROVIDE_CLOCK message. We used to check if we were acquired but that doesn't
work anymore now that we do the negotiation async in the streaming thread: it's
possible that we are still negotiating when the pipeline asks us for a clock.