VideoFilters using AccelerationFramework (Feature #2135)

The VideoFilters project is stable, but you can already notice that some filters are really slow in OpenCV.

Acceleration framework provides CPU optimized DSP functions, for example convolution.

As a guideline I would say, that it only makes sense to replace code with wrappers. If I had to generate for example a Gaussian kernel manually from scratch in order to convolve with Acceleration, we'll end up with two implementations of Gaussian convolution. The guideline in this case should be: have an OpenCV function that creates the kernel and then copy the data and run accelerated convolution.

I am not sure this task will be very successful, as many thinks can't be simply wrapped. And finally, to make use of low level vector operations, we would have to dig very deep into OpenCV functions.