feat: configurable git repository root

[frankdugan3]

Contributor checklist

• [ x ] My commit messages follow the Conventional Commit Message Format
  For example: fix: Multiply by appropriate coefficient, or
  feat(Calculator): Correctly preserve history
  Any explanation or long form information in your commit message should be
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• [ x ] Bug fixes include regression tests
• [ x ] Features include unit/acceptance tests (partial!)

I tried to organize my commits neatly, there's clear separation of chores along the way and the feature itself.

No tests are broken, and I added one test to check for the default repo value of cwd. I'm not sure how to test for the custom git repo, so I'm thinking for now this can be a "here be dragons" feature. I did not add documentation for this reason as well, but would be happy to do so if you think that's a good idea.

I did test this on one of my poncho/nerves projects and it seems to be working correctly.

As always, open to nitpicking/refactoring.

Closes: #52
Closes: #37

[zachdaniel]

Looks good, had a couple questions that may need addressing, but otherwise awesome!

[zachdaniel]

🚀 Thank you for your contribution! 🚀