Write Python bindings for CCExtractor

Extend Python to use CCExtractor's library to access subtitles. You should export as much of CCExtractor as possible. At a minimum, it should be able to

- Open and close input video streams.
- For an open stream, get the list of programs.
- For a selected program, get the subtitles in various easy to use structures. You need to provide access to the original representation (for example, if it's US TV subtitles then a grid for CEA-608, if it's European DVB subtitles then a bitmap) as well as the conversion to usual formats such as .srt.

While CCExtractor itself uses its own library (lib_ccx), we are not aware of any other program using the library directly (as opposed to running CCExtractor and getting the generated file). This means - it's likely you will also need to modify the library itself to make it “sane enough” for this project.

Related GitHub Issues
Make the Python Scripts to run Python3
Python Bindings don't compile with build_library