Language-tool-python

- allow language_tool_python to run in multiple disparate processes on the same machine (just use different ports)
- new syntax for error correction: `tool.correct(text_with_errors)` (no need to provide `List[Match]` anymore)
- run tests using github test runner to verify things work on multiple python versions

- Add `LTP_PATH` environment option to customize LanguageTool server location
- Change download URL environment option to `LTP_DOWNLOAD_HOST`
- Downloading supports a wider array of Python versions
- Add `tqdm` (our first dependency!) for a nice progress bar