- Previous version just checked option support, but not enable it.
- Also OpenCV tests reports invalid AVX and AVX2 support status.

if `Scalar:all` is used, Mats with 5+ channels cause errors

Because apparently I love running performance tests for debug builds.

That way, core/internal.hpp doesn't have to depend on cvconfig.h, which we
don't ship.

Namely, normalize their names to a common convention and remove useless text
from their values.

cmpEps replaced on cmpEps2 to reduce code dublication;
Constants for cmpEps return values added.

added COVAR_ and SORT_ enums to core.hpp; fixed many, many VS2005, VS2010 and MinGW (GCC 4.5.2) warnings

a big patch; use special proxy types (Input/OutputArray, Input/OutputArrayOfArrays) for passing in vectors, matrices etc.

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