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.

#ignore
Merge branch 'master' of https://github.com/textmate/prolog.tmbundle
Tweak a few things--DCGs, curly brackets, comment behavior, file extensions--and add some AnsProlog feature support.