Mavericks fixes

- Ruby version bumped to 2.0.0
- Alfred gem bumped to 2.0.5 (added more dependencies)
- Project directory added to ``LOAD_PATH`` in ruby files with local, relative references
- Symbols used (over strings) with hashes
- Correct use of ``alfred.settings``

All the deleted files are from the Ruby 1.8 gems. Not sure of the backwards compatibility of this.