The test works by using a parse transform that stamps modules with an
attribute as it runs them. It then compiles everything, loads the
module, and makes sure the stamps respect the defined order.

get correct compile paths included in module info

fixes #216 and #220

pre-purging before checking to facilitate long do chains

fixes #175

arguments to ensure compile results as as intended

Now supports arbitrary commands

- Adding tests
- fixing use of set fetching to find repeated deps and prevent infinite
  loops

On a circular loop rebar3 now fails with `{error, no_sort}`, which is
uncaught and should be handled to consider the issue fully fixed.

- Reworked the helpers for existing suites and expanded them
- Created a mock git resource module to test for its dependency fetching
- Added a test suite for dependency resolving with first checks for
  common cases (https://gist.github.com/ferd/197cc5c0b85aae370436)

Left to do would include:

- Verify warnings
- Verify failures
- Verify dependency updates resolving