Re-enable old FFmpeg's VDPAU API for non-nvidia drivers

This is a partial reverse of a5b996c06dd73b378b39bbc772183c4abf53e4d7.
The new FFmpeg hwaccel API causes issues with non-nvidia drivers, causing either crashes (nouveau drivers) or playback issues (AMD).
So only use hwaccel with NVIDIA native drivers.
As of today (2014-05-20) The Ondine_clip.mpg doesn't play with any non nvidia drivers anyway (ref #11377)

This is a very direty solution, I don't like it but I couldn't find a universal solution working on all platforms at once.
Hopefully, hwaccel in FFmpeg 2.x works better
Don't attempt to test for GPU decoding methods once one has ben found

It is now possible with video cards such as AMD to have support for both VAAPI and VDPAU; which would cause myth to attempt to use both at once.
There's also no need to test for GPU methods if hardware decoding is disabled.

Simplify code while at it.

(cherry picked from commit 5002c1ca51ec8ed9367e54a517e1ad4f378fff78)
Update ABI version
Don't unnecessarily retune Ceton and HDHomerun Prime when using
multirec.

Previously, when using multirec on a Ceton or HDHRP tuner and a second
recording started, the channel would be retuned and cause a small
disruption in the first recording.  This change doesn't perform the
useless retuning avoiding the disuption on the first recording.

This fix was originally developed by John Poet with a couple of fixes
by me after testing.
Fix FreeBSD 10 builds of zeromq. We have to run autogen.sh otherwise shared libs get disabled
Add method to check if VPDAU is supported
Fix VDPAU being always used when present even if not working (test was always true)

If VDPAU was installed, but not working (like on an intel machine with also VAAPI support), VDPAU would be used regardless
Simplify VDPAU support detection, no point checking for features if basic detection has failed.
Fix memory leak
Revert "Fix memory leak"

This reverts commit fadcad406cc14092c3089ea5539dc41ec1221b49.
Fix memory leak
ExternalStreamHandler: better handling when unable to write complete command
to external app.
Cleanup some whitespace
OSD: use 'short' timeout for seeking type event notifications
unbreak flush_deleted_recgroup.pl
zeromq configure also requires autoreconf

Stop configure should zeromq/autogen.sh fails
cppcheck: Invalid usleep() argument. The value is 1000000 but the valid values are ' 0-999999' .
cppcheck: fix format string signedness
Speed up ProgramInfo::SavePositionMap() database writes.

Use a single SQL query to save all new position map entries.
This speeds up SavePositionMap by an order of magnitude.

Fixes #12016

Signed-off-by: Jean-Yves Avenard <jyavenard@mythtv.org>
Speed up writing EIT cache to database

Use a single SQL query to write EIT cache to database rather than a series of queries. This significantly speed up disk operations

Ref #12016

Signed-off-by: Jean-Yves Avenard <jyavenard@mythtv.org>
Don't unecessarily query the backend if we don't need it

No point attempting to skip a commercial if there are none to skip.
This prevents querying the backend for an up to date frames count

Ref #12016

Signed-off-by: Jean-Yves Avenard <jyavenard@mythtv.org>