Use version 1.8 of ruby for bundle items

10.7 and 10.8 only include ruby 1.8, so all bundle items have been
written to work with that. Optionally supporting ruby 1.9 and 2.0 is
problematic as these versions are not fully backwards compatible.

Using a shim allows us to catch when 1.8 of ruby is not present and
provide other options.

#ignore
Merge pull request #4 from syscrusher/pr/3

Use version 1.8 of ruby for bundle items
Implements https://github.com/syscrusher/golang.tmbundle/pull/3