Fully embrace Ruby 1.9 hash syntax

Created by: rspeicher

Didn't bother with files in db/, config/, or features/

I realize this is a huge commit. Let me know if breaking it up by directory or something would help.

For reference, accomplished with these commands:

perl -pi -e 's/([^:]):([\w\d_]+)(\s*)=>/\1\2:/g' app/views/**/*.haml
perl -pi -e 's/([^:]):([\w\d_]+)(\s*)=>/\1\2:/g' **/*.rb