agingtv: fix memcpy when no color aging requested.

video_size is the size in pixels, actual size of the memcpy
has to be stride * height.
rtph264pay: Fixes buffer leak when using SPS/PPS

Fixes a buffer leak that would occurr if the pipeline was shutdown
while a SPS/PPS header was being created.

https://bugzilla.gnome.org/show_bug.cgi?id=741271
v4l2bufferpool: set buffer interlace flags when field is V4L2_FIELD_INTERLACED

If v4l2_buffer.field is V4L2_FIELD_INTERLACED, we set corresponding
GstVideoBuffer flags depending on the video standard.
According to V4L2 specification, M/NTSC transmits the bottom field
first, all other standards the top field first.

https://bugzilla.gnome.org/show_bug.cgi?id=737603
rtpsession: Use an empty iterator in iterate_internal_link when no links

And not a NULL Iterator, so it is consistent with the way it usually
works and avoid user to need a different code paths to handle that.
vpXenc: CLOCK_TIME_NONE is not a valid min_latency value

We should just use 0 if we do not have the information