Activate ml module Python bindings in 3 release (Bug #4033)

<tempassoc> When I compile opencv 3, cv2.ANN_MLP isn't there.
<tempassoc> Why?
<tempassoc> When I compile opencv 2.4.9, cv2.ANN_MLP is there and usable.
<tempassoc> Compiling opencv 3-beta

<tempassoc> I just enabled a bunch of things on the command line of "cmake .."
<tempassoc> and am now rebuilding, and seeing if that works.

<tempassoc> Oh ok, all the machine learning stuff is at cv2.ml in opencv3

<gliese581h> tempassoc: there was some major refactoring of the 3.0 ml module, and they had to disable the script wrappers temporarily. what you see in cv2.ml are only the enums/constants, no classes or functions.
<tempassoc> Acknowledged, thank you.
<tempassoc> I hope it's something that will be resolved by release.
<tempassoc> I'll stick with 2.4.9 for now then.

Please activate the Python wrappers for OpenCV 3.