Python: Enable opencv to act as installable module

 * introduce a setup.py file to enable pip installs
 * compile opencv statically into the loadable module
   so that each virtualenv can have its own
   opencv installation.

What works:

 * pip install git+https://github.com/stylight/opencv#egg=opencv into a virtualenv
   this enables other modules to specify opencv as a dependency and get it resolved
   automatically (given the build dependencies are met)

Known Bugs:

 * "pip uninstall opencv" fails to remove cv2.so
 * uploading to pypi not tested and probably doesn't work yet.
 * missing build dependencies are probably not handled gracefully.

TODO

 * cmake/make failures should be handled gracefully. Here we have 2 possible
   sources of the failure: missing some required tool/library or a problem in
   the library itself. In the latter case user needs to be prompted to report
   a bug. Also it is important to make a graceful exit on Windows which is not
   supported at the moment.
 * replace your fork url with upstream address