Pyedgar

Update CLI functionality.

- `__main__.py` is the new entry point, replacing `downloader.py`.
- Index and feed functionality were separated
- `end_date` arguments were added to the download functions
- `-x` argument added to extract feed files.
- `-d` argument changed to just download feeds, not extract them.

Fix carriage return bug

Add year/quarter formatting to FEED CACHE format.

Testing PyPI CI, bumped copyright date.

**Full Changelog**: https://github.com/gaulinmp/pyedgar/compare/v0.1.9...v0.1.10

Changes (not complete probably, I'm bad at this):

- Update Filing object to be more useful
- Check Indices object has a df (fixes 8)
- Update default User Agent in config file to not have example.com email, which may have broken things (mentioned in 8)
- Add Github Action to hopefully push this automatically to PyPI. 20$ says it doesn't work.

**Full Changelog**: https://github.com/gaulinmp/pyedgar/compare/v0.1.6...v0.1.9