cvvideofilter: Check buffer_map return value

Check the resturn value and cleanly fail if we could not mapped the buffers.

https://bugzilla.gnome.org/show_bug.cgi?id=732756
cvvideofilter: Don't try to make buffer writable

First this is handle by base transform, hence this is a no-op, and if it wasn't it
would lead to a buffer copy being leaked, and then an unreffed buffer being
pushed downstream.

https://bugzilla.gnome.org/show_bug.cgi?id=732756
faceblur: Port to OpencvVideoFilter base class

This fixes issue whit black frames when special memory, like GlMemory is
in used.

https://bugzilla.gnome.org/show_bug.cgi?id=732756
handdetect: Move size warning in set_caps so it's called once
handdetect: Use already mapped image

No need to map again the image, it's already handled by the base class.
facedetect: Make cascades dir a little more portable
aggregator: fix locking

We would unlock a mutex we never locked on SEGMENT
events.
videoaggregator: fix broken locking in update_src_caps function

We would unlock an already-unlocked mutex that we never re-locked.

https://bugzilla.gnome.org/show_bug.cgi?id=732750
videoaggregator: Fix some more the locking logic in update_src_caps

We need the GST_OBJECT_LOCK only to iterate the sinkpads, nothing else.

https://bugzilla.gnome.org/show_bug.cgi?id=732750
mpegts: fix leak of language code
mpegts: atsc: fix leak of short name
mpegts: Add padding to public structures

Allows use to add API in the future without breaking ABI. We broke the API/ABI
once between 1.2 and 1.4, let's try to avoid this in the future even if this
is an unstable library.

https://bugzilla.gnome.org/show_bug.cgi?id=730914
mpegts: fix annotation

https://bugzilla.gnome.org/show_bug.cgi?id=730914
mpegts: docs: add missed *_free methods

https://bugzilla.gnome.org/show_bug.cgi?id=730914
mpegts: use getter for egde linkage descriptor type

https://bugzilla.gnome.org/show_bug.cgi?id=730914
mpegts: Fix dvb linkage leaks

CID #1224130
mpegts: Don't confuse slice allocator with regular one

Previously selector_bytes and private_data_bytes were sometimes allocated and
free using the normal allocator and sometimes using the slice allocator.
Additionally prefer g_strdup() to g_memdup() for strings.

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=732789
mpegts: No need to check for NULL before calling g_free()

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=732789
glimagesink: Keep aspect ratio by default

The expected default behaviour for video sink is to maintain the
aspect ratio. Fix the default value to reflect this. The property
default was already TRUE, but the value was not initially TRUE.
tests/icles/dccp: Release reference to parent

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=732977