rtspsrc: fix seeking

Call gst_rtspsrc_connection_flush (src, FALSE) to reset connections as
non-flushing before sending PAUSE and PLAY with the new npt range. Without this
patch, those commands would fail with EINTR as the connections were still
flushing.
session: handle unknown SSRC in FIR

https://bugzilla.gnome.org/show_bug.cgi?id=725712
session: small cleanups

It's nicer to explicitly check for NULL on pointer types to make it
clear that it's a pointer and not a boolean.
rtspsrc: handle NULL control urls better
Add docs directory to spec file
osxvideo: fix build on Mac OSX Mavericks and put new window in front

GetCurrentProcess/SetFrontProcess/TransformProcessType was deprecated
and now removed in Mac OSX 10.9. orderFrontRegardless is used to make
the video window the most front window.
rtspsrc: just use the SDP index as the stream id

Use the index of the media stream in the SDP as the stream id instead of
keeping a separate counter.
rtspsrc: remove obsolete code
rtspsrc: skip streams with same control url

Keep track of what streams we did the SETUP for. We only need to
configure caps, wait for pads and push events on setup streams. We can
remove the disabled state of the stream and simplify some checks.
After we setup a stream, skip the other streams that have the same
control url. Use a skipped flag to mark streams that should be skipped.
souphttpsrc: If we had a stop position, allow for the server to finish our connection instead of just cancelling

Otherwise keep-alive does not make much sense and also the server will have
confusing things in the logs.
souphttpsrc: Don't forget to quit mainloop after we cancelled when we got data after the stop position
rtpspeexdepay: Remove caps restrictions for depayloader

The "encoding-params" is optional in the SDP, because we now require
a subset of the caps, it would fail caps negotiatioin if it wasn't present.
So removed it from the template caps.
rtp: Remove caps restrictions from RTP depayloader sink caps

Remove caps restrictions that correspond to the default and are not
required in SDP. With the new usage of having pads require a subset
of the caps, they will make the negotiation fail.