Fixed Ruby 1.8 path problem

Ruby 1.8 is no longer installed on the latest OS X. Because of this, this
bundle doesn't work anymore. I replaced the full path to the interpreter
with the env command.

Gianluca Andreotti <gianlucaatlas (at) gmail (dot) com>
Merge pull request #3 from buglite/master

Fixed Ruby 1.8 path problem