karma.conf.js update for Karma 0.10.4

The conf file format changed. Also there is a "bug" at the moment where the html2js preprocessor is automatically on, so we need to include an empty preprocessors object to allow us to serve our html fixtures.
Require karma 0.10 or later for correct testing on Travis
Fix warning in karma.conf.js
Update README to mention BrowserStack for cross-browser testing
Merge branch 'refs/heads/develop'