matroskademux: Don't print warnings during flushing and stop as soon as possible

https://bugzilla.gnome.org//show_bug.cgi?id=705442
avidemux: send proper stream_start event

https://bugzilla.gnome.org//show_bug.cgi?id=705449
videomixer: Send EOS if buf_end >= segment.stop

That means the whole segment is already played, and we are sure we
are EOS at that point.

Also handle segment seeks, and do not send EOS in that case.
qtdemux: elst should offset samples instead of buffers

The current approach where buffers are offset is not ideal, as during seek
and loop current time is compared to sample times.

https://bugzilla.gnome.org/show_bug.cgi?id=700264
souphttpsrc: add redirection to the URI query
souphttpsrc: fix critical setting a NULL uri redirection
rtspsrc: Only free GCheckSum after its last usage

https://bugzilla.gnome.org/show_bug.cgi?id=705760
aacparse: allow conversion from raw AAC to ADTS

This patch will prepend ADTS headers to raw AAC audio frames, allowing
upstream elements to link to decoders that only support AAC in ADTS format.

Note that no error correction bits are added to ADTS frames in this code.

https://bugzilla.gnome.org/show_bug.cgi?id=615740
rtph264depay: Make the SPS/PPS deduplication function generic

Make it not touch any internals of the depayloader

https://bugzilla.gnome.org/show_bug.cgi?id=705553
rtph264pay: Use the SPS/PPS handling function from the depayloader

Remove duplicated copies

https://bugzilla.gnome.org/show_bug.cgi?id=705553
.gitignore: Ignore files from automake test-driver
soup: don't use deprecated soup_message_headers_get() API
configure: require libsoup >= 2.38

Bump libsoup requirement for newer API used, like headers_get_one().
2.38 is from early 2012 and is in linen with our GLib requirement.
jitterbuffer: forward flush before stopping dataflow

First forward the flush event and then stop our loop function.
ext: Use new flush vfunc of video codec base classes and remove reset implementations
qtdemux: check denominator isn't zero before scaling duration.

When gst_qtdemux_configure_stream sets fps_d, check that n_samples is
non-zero before using it as a denominator to scale the stream duration.

https://bugzilla.gnome.org/show_bug.cgi?id=706076
flacenc: Properly set headers via the base class instead of just pushing them downstream

Prevents buffers from being send before the caps and segment events.
h264depay: init debug category early

Init the debug variable when we register the element because it is also used by
the payloader element when it calls the add_sps_pps method.
videomixer: Do not send flush_stop ourself after a flush_start

When we receive a flush_start, we should wait for the next flush_stop
and foward it, not create a flush_stop ourself.
v4l2: Use G_DEFINE_ macros for added thread safety