Refactor Brocfile.

* Remove vendored code from repo (in favor of bower config).
* Update `version` in `package.json` to include `+` (so we get nice
  per-commit version numbers).
* Move `test/tests/` into `tests/`.
* Move `lib/calculateVersion` to `config/calculateVersion` (otherwise
  our transpiled output includes `calculateVersion` which is really only
  a build tool not part of backburner itself).
* Generate concatted named AMD build.
* Add custom require for test modules (in tests/index.html).
* Add test-loader (to auto-require AMD modules ending with `-test`).
* Add jshinting to broccoli build.
* Update `testem.json` to match what is required for `ember test` and
  `ember test --server`.
* Update `package.json` to use `ember build`, `ember test`, and `ember
  test --server`.