Previously the function requires Info::Impl implicitly. A call will create
new Context this function which is not intended.
The properties are now moved to global scope to fix this issue.

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

Turns out, you can't use preprocessor directives inside macro arguments.
Who'd have thought?

* In comparison column headers, switched the order of labels, so that
  it's "to" vs "from".

* When a test was present, but not run successfully, put its status in
  the corresponding cell instead of coloring it gray.

The bug was found that all 3-channel oclMat's were converted to
4-channel oclMat's after using convertTo function.

Now it allows choosing between arbitrary implementation variants.

I don't know why it didn't work for the original author, but it definitely
works now.

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

There is no WIN64 defined in the environment.