New Types + Variable Resolver

[ncilfone]

What does this PR do?

• Added support for new fundamental types: (1) file: this is an overload of a str that verifies file existence and (r/w) access (2) directory: this is an overload of a str that verifies directory existence, creation if not existing, and (r/w) access
• Added support for resolving value definitions from references to other defined variables with the following syntax,${spock.var:SpockClass.defined_variable}. Closes Interpolation and Accessing environment variables and other resolvers inside the config.yaml similar to OmegaConf #243
• Deprecated support for List of repeated @spock decorated classes.
• Updated docs.
• Fixes detecting cycles in graphs.
• Fixes Nested List, Tuple error #260 and issues with Tuples enforcing len and checking type.
• Bumped black support for 3.10.
• Added pre-commit hooks.
• Updated linter.

Checklist

• Did you adhere to PEP-8 standards?
• Did you run black and isort prior to submitting your PR?
• Does your PR pass all existing unit tests?
• Did you add associated unit tests for any additional functionality?
• Did you provide code documentation (Google Docstring format) whenever possible, even for simple functions or classes?
• Did you add necessary documentation to the website?

[coveralls]

Pull Request Test Coverage Report for Build 3912745148

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 432 of 453 (95.36%) changed or added relevant lines in 11 files are covered.
• 28 unchanged lines in 6 files lost coverage.
• Overall coverage decreased (-0.8%) to 95.166%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
spock/backend/resolvers.py	74	75	98.67%
spock/utils.py	5	6	83.33%
spock/backend/typed.py	15	17	88.24%
spock/graph.py	164	168	97.62%
spock/backend/validators.py	81	94	86.17%

Files with Coverage Reduction	New Missed Lines	%
spock/backend/builder.py	1	99.11%
spock/graph.py	1	97.41%
spock/backend/resolvers.py	2	97.37%
spock/backend/saver.py	4	95.65%
spock/backend/utils.py	5	92.92%
spock/backend/payload.py	15	82.88%

Totals
Change from base Build 2511258184:	-0.8%
Covered Lines:	2461
Relevant Lines:	2586

---

💛 - Coveralls

[ncilfone]

@brianwarner Need reviewer approval for merge to master. Also can't cut a new release via a tag (which will trigger the build/push to pypi) since I don't have permissions. This should be the 3.0 release as there is a non backwards compat feature.

Any chance you've figured out Fidelity's view on outside collaborators being able to review/merge/release? Need a path to sustainability here as I've picked back up development... Trying to avoid forking spock and maintaining it outside of Fidelity OSS