Merge branch 'develop' of https://github.com/yanoh/r2 into develop

Conflicts:
	Gemfile
	Gemfile.lock
Add acceptance test
Add more scenarios of acceptance test
Add more scenarios of acceptance test again
Add acceptance test
Add more scenarios of acceptance test
Add more scenarios of acceptance test again
Merge branch 'yanoh-add_test-acceptance' of https://github.com/yanoh/r2 into yanoh-add_test-acceptance

Conflicts:
	test/integration/acceptance_test.rb