Bundle ci_reporter_test_unit that was extracted from ci_reporter recently

https://github.com/ci-reporter/ci_reporter/commit/5b01f524c521914d577998e57cf5252ebac2666d
simplecov supports ruby 1.9+ only
Seems like ci_reporter 2 dropped Ruby 1.8 support
Merge pull request #209 from amatsuda/ci_reporter_test_unit

Bundle ci_reporter_test_unit that was extracted from ci_reporter recently