add rspec filter 'focus' and 'skip'

It allows you to run only specific tests or exclude some specific tests. This is helpful to focus on the tests for the current working feature. If all focused tests runs, rspec will do a second full run, so it is ensured that no test is broken.

See https://www.relishapp.com/rspec/rspec-core/v/2-0/docs/filtering for more informations