Add namespace bgsegm, replacement functions and Template class for new
OpenCV versions because these functions have been removed. cvarrToMat() is
added because it is compatible with all versions of OpenCV and the use of
class Mat constructor is eliminated, it is also deprecated in 3.X versions.
Use the namespace cv because some functions are called many times.
This patch keeps compatibility with 2.4
https://bugzilla.gnome.org/show_bug.cgi?id=760473
The opencv element includes were full of duplicates and uneeded headers.
For example a few elements that stopped using gstcvopencvutils still
included that header file.
If old opencv1-style legacy include directory is available,
this change becomes purely cosmetic (maybe will compile a bit faster).
It becomes an FTBFS fix when opencv1-style include directory is missing
(possibly because opencv package maintainer decided not to pack it).
https://bugzilla.gnome.org/show_bug.cgi?id=747705
Fixes:
In file included from gstsegmentation.h:51:0,
from gstopencv.c:42:
/usr/include/opencv2/video/background_segm.hpp:47:16: fatal error: list:
No such file or directory
#include <list>
^
compilation terminated.
https://bugzilla.gnome.org/show_bug.cgi?id=702297
