Update dependencies.

No Issue
- bluebird@2.3.10
- bookshelf@0.7.9
- fs-extra@0.12.0
- semver@4.1.0
- grunt-ember-templates@0.4.23 (remove direct dep on ember-template-compiler)
- grunt-sass@0.16.1 (remove direct dep on node-sass)
- remove direct dependency on mocha (only used via grunt-mocha-cli)