Remove the --force option from the grunt command

This was causing grunt to treat failures in the jasmine:local task tests as warnings resulting in successful builds despite failing tests.
Merge pull request #195 from cbmi/fail-on-test-failure

Fail travis-ci build on test failure
Merge branch 'develop' into 2.1

There isn't much to merge but I wanted the new travis-ci file here and didn't
want to duplicate the changes with another commit on the branch.