Merge pull request #25 from matthew-james/develop

prevent error when sorting by a column with unset option text
YAML doesn't like tabs, and I don't blame it
Updating travis and karma-ci config
Removing stopPropagation so users can listen to owlTableUpdated event
Merge pull request #26 from onijim/feature/propagate-changed-event

Removing stopPropagation so users can listen to owlTableUpdated event