remove opencv1 dependencies.
bgslib now compiles on Linux systems without libcv-dev installed.
Almost all calls and incudes have been ported to opencv2, some are
still used via opencv2/legacy/compat.hpp (e.g. cvFillImage).
Hope I got everything fine also for mingw since I removed two
mingw related defines.
I don't have a mingw install to check it against.
FrameProcessor.cpp: use MultiLayerBGS::Status as enum and not as class (required for some picky compilers)
Merge pull request #9 from holgerfriedrich/master

remove opencv1 dependencies.