Prepared base for application.

Added couple of handy gems for development and tests. Setup rspec helper
files and basic structure. Add some support files for tests like db
cleaner, i18n errors on missing translation, and devise helpers. Also
added first sanity check spec.

For views use bootstrap for basic sane look, and haml for markup.
Added landing page & go green with sanity check spec.
Added tests for users
Added users with devise
Added basic specs for gadgets