Add support for Travis CI
Remove separate Gemfile for Travis to ensure the same environment everywhere
Add Code Climate badge
Add Coveralls
Add Coveralls badge to README
Add coveralls and its dependencies to Gemfile.lock
Add Headless gem to run WebKit on Travis
Remove actual DB config, leave only an example config file for PostgeSQL
Add separate DB config for Travis
Ignore local DB config, let every developer modify it to their needs
Optimize item tags retrieval. Thanks @av-ast !
Execute Coveralls on Travis, otherwise SimpleCov.