co-existence with python-rarfile, and using system libunrar without pip/installing

[HinTak]

I have an issue with extracting non-unicode multibyte filenames:
markokr/rarfile#28
so I thought interfacing with libunrar might be a better design.

Unfortunately I don't/can't seem to get this to work. Also, I already have libunrar and dev headers on the system, and prefer not to use pip, so basically I just like to set PYTHON_LIBRARY_PATH and run this without installing.

I think running without installing is important for anybody at a 'trying this out' stage. Giving only pip instructions seems unwise.