Revert "Merge pull request #29 from edx/chore/markchang/replace-rvmrc"

This reverts commit d97009d10971d1d88d3c4de881d7a0d5da9bcaa7, reversing
changes made to a9d281adc3b61c17cf071385530118faae46934e.
Merge pull request #57 from edx/jarv/revert-pull-29

Revert "Merge pull request #29 from edx/chore/markchang/replace-rvmrc"