1. Unskip some trivial tests that were being tested higher up
2. Istanbul ignore some code for coverage.
1. Things that I didn't write and need to 100% follow
2. The source code checking test that has Istanbul code injected into
it
3. Add a few simple test cases
4. Support passing port numbers through to `ember serve` and `ember
test` for use cases that would benefit from being able to configure the
ports things are served over but still use `yarn run` thus reusing the
`yarn run` config in `package.json`