Rewrite the crate

[funnyboy-roks]

This is basically a full rewrite of the crate, now that we've used it and noticed issues.

There are a few important points that I'm trying to accomplish with this rewrite that were missing from the original:

• A test context can be created once at the start of a long-running application. This context contains all of the generic information that applies to any test suite (i.e., tests, required files, compile/run commands)
  • From this context, individual test runners can be created for actually running the tests. These test runners should be able to specify what subset of tests will be run
• Running tests should be fully asynchronous. This was the case before, but I want to take it to another level by allowing test status to be updated in any order.
  • For example, if test1 takes 50ms and test2 takes 25ms, then we should get the result of test2 before test1.
  • This should work in the same way that JoinSet works, with a join_next-equivalent function that will return the next finished test.

This will also close #2, #6, and #7.

Major TODO items:

• Create type-state builder for TestContext
• Actually run tests
• Add useful logging
• Add serde derives where logical
  • Decided against using serde for this as it doesn't really work well for a lot of the types. Mapping from other types is simple enough, so that's left to the consumer.
• Copy directories
• Add support for various output validation
  • Regex
  • Multiple Strings (? - Not sure if we need this on top of regex)
    Opting against this for now, we may want to re-evaluate at a later point in time.
• Write Tests
  • At least 95% coverage since we have codecov now
• Cleanup API (i.e., make every function useful, reorganise modules)
• Add documentation

[codecov]

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[jackjohn7]

Love this so far!