Added unit tests to prove that the ruby-units variant works (it is broken now)
ruby-units style basic temperature conversion working, math unit tests still failing
Fixed a broken unit test
Finished ruby-units branch (now passing all unit tests)
cleanup
I missed some cases from ruby-units (added new failing tests)
added new tests for some missed ruby-units cases and updated to pass the tests
Updated readme
missed a spot
added a blurb about inverses
minor change