Add unit tests to list of files to measure for code coverage
Add unit tests to list of files to measure for code coverage

* Exclude all other kinds of tests for measuring code coverage. Other kinds of
  tests like integration tests give a false sense of how much code is actually
  covered because it's very easy to cover large parts of the codebase with just
  a small handful of integration tests.

nepalez/ice_nine,dkubb/ice_nine,soulcutter/ice_nine