Removed MongoDB dependency by adding Flapdoodle embedded MongoDB. That allows us to get rid of the utility module we had in place for the MongoDB samples guarding the tests to only run when a MongoDB instance is running.
Tweaked Travis setup to not require the MongoDB service anymore.
Remove online resources and just rely on local data. Though we had to keep the BlogPostInitializer for setting up the tests only using the template without repository support.
Original pull request: #18.
