Add Karma unit tests

Added Karma Unit test for AngularJS controllers/ and services/
Moved existing tests into test/mocha/
Karma will create a test/coverage/ report folder which is .gitignored
Karma is set to use PhantomJS but is easily changed to Chrome (or other brower via config)
Karma configs are kept in a separate file rather than in gruntfile.js

If all good can look as adding in some Karam e2e tests and also API tests using mocha w/ supertest.

Thanks.