Tox-poetry-installer

- Add default installation of locked dependencies using thread workers, decreasing
environment provisioning times by ~90%
- Add runtime option `--parallel-install-threads` to support configuring the number of
worker threads for parallel dependency installation
- Add configuration option `install_project_deps` to support disabling the install of
project dependencies to an environment
- Deprecate runtime option `--parallelize-locked-install`

- Add runtime option `--parallelize-locked-install` to support installing locked
dependencies in parallel to speed up test environment creation
- Add config option `require_poetry` to allow per-environment control over whether the
plugin should force an error
- Add unit tests for custom dependency processing and installation
- Update internal logging system to reduce code duplication
- Update documentation to improve readability
- Deprecate runtime option `--require-poetry`

- Remove custom package compatibility checking logic from transient dependency resolution
process
- Add integration with Poetry's compatibility
[`Marker`](https://github.com/python-poetry/poetry-core/blob/master/poetry/core/version/markers.py)
object system for determining package compatibility with the current platform
([43](https://github.com/enpaul/tox-poetry-installer/issues/43))
- Add missing PyPI classifier for Python 3

- Update required `tox` version from `^3.0` to `^3.8` to avoid compatibility issues
- Update logging messages to improve UX
- Fix transient dependency packages being installed in a pseudo-random order due to Python
sets being unordered ([41](https://github.com/enpaul/tox-poetry-installer/issues/41))
- Fix outdated docstrings

- Update locked version of `py` to `1.10.0` to address
[CVE-2020-29651](https://nvd.nist.gov/vuln/detail/CVE-2020-29651)
- Fix dependency identification failing when the package under test is a transient
dependency of a locked dependency specified for installation
- Fix `AttributeError` being raised while creating the Tox self-provisioned environment
when using either the
[`minversion`](https://tox.readthedocs.io/en/latest/config.html#conf-minversion) or
[`requires`](https://tox.readthedocs.io/en/latest/config.html#conf-requires) Tox config
options

- Update logging around transient dependency processing to improve debugging of dependency
installation problems
- Fix regression around handling of Poetry's unsafe packages when the unsafe package is a
transient dependency ([33](https://github.com/enpaul/tox-poetry-installer/issues/33))
- Fix handling of Poetry's unsafe packages when the unsafe package is a primary
(environment or package) dependency