Refactor most data manipulation into helpers
Clean up
Fix tests
Merge pull request #23 from praekelt/feature/issue-23-data-helpers

Take a more OO approach to handling the d3 data
Add travis config.
Add karma phantomjs launcher and use it for tests.
Merge branch 'develop' into feature/issue-24-add-travis
Fix phantomjs launcher version.
Fix menuComponent test to work with PhantomJS (thanks @andreit).
Merge branch 'feature/issue-24-add-travis' into develop
Merge branch 'develop' into feature/issue-10-connection-direction
Calculating arrow rotation