* Adds support for pyproject.toml files
Since mypy 0.900 the pyproject.toml files are supported.
This PR adds a support for it. It searchs for a `tool.django-stubs` section. This is an example configuration:
```
[tool.django-stubs]
django_settings_module = "config.settings.local"
```
Fixes#638
* Added TOML tests
* Use textwrap.dedent instead of trying to manually replace spaces
* run black
* create monkeypatching function for adding get_item dunder
* whoops i forgot the test
* change the name in INSTALLED_APPS to make test pass
* turn the whole thing into a proper package
* move django_stubs_ext to requirements.txt
* also install requirements.txt
* attempt to fix pre-commit
* numerous small code review fixes
* fix dependency issues
* small dependency fixes
* configure proper license file location
* add the rest of the monkeypatching
* use strict mypy
* update contributing with a note monkeypatching generics
* copy release script from parent package
* Updated gitpython dependency to fix error:
ModuleNotFoundError: No module named 'gitdb.utils.compat'
* Updated Django repository git refs because old 3.0.x commit hash gave error:
stderr: 'fatal: reference is not a tree: 6cb30414bc0f83b49afc4cae76d4af5656effe9a'
* Newer Django version also needs new ignores.
