Add MyPy stubs

[edthedev]

Context

When we import this library from our ClearPass SOAR app, our CI/CD test suite gives a MyPy warning.

Task List:

• [ ] Add a Makefile
• [ ] Add MyPy to the test step in the Makefile
• [ ] Add type declarations until the tests pass
• [ ] Remove the MyPy Exception from the SOAR ClearPass App and retest

[mpitcel]

This issue blocks #5