Add support for Boost.Python

[jcarpent]

Thanks a lot for this nice toolbox.
As I'm mostly using Boost.Python, I have added the possibility to parse libraries compiled with Boost.Python.

I'm open to any change if needed.
Thanks in advance for the review,

Best,
Justin

[codecov-commenter]

Codecov Report

Merging #57 (3e6c313) into master (8dc031a) will decrease coverage by 6.89%.
The diff coverage is 7.54%.

@@            Coverage Diff             @@
##           master      #57      +/-   ##
==========================================
- Coverage   90.80%   83.90%   -6.90%     
==========================================
  Files           2        2              
  Lines         587      640      +53     
==========================================
+ Hits          533      537       +4     
- Misses         54      103      +49     

Impacted Files	Coverage Δ
pybind11_stubgen/__init__.py	83.83% <7.54%> (-6.93%)	⬇️

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[sizmailov]

Hi, thanks for interest to the project.

I don't like idea of including plenty of new code without tests. At the same time adding new binding framework like boost.python would require quite a bit of time to set up, and probably that is me who should do that.
Unfortunately I don't have time for that at the moment, so can't promise any ETA.

Note: Did you try stubgen from mypy? It should work well for boost.python

[sizmailov]

The PR targets the obsolete version of the library, there I'm closing it. The main problem with this was the lack of tests.