Enable "availability_zone" configuration

Fix #27
update functional tests
Shellcheck on run_tests.sh
disable functional tests in travis for now
rubocop compliant vagrantfile
clean functional tests
vagrant up works with different machine states

Fix #57 #56
Rubocop style
Merge branch 'master' into issue#51

Conflicts:
	source/Gemfile
	source/gemfiles/latest_stable.gemfile
	source/gemfiles/oldest_current.gemfile
	source/gemfiles/previous_release.gemfile