update user logup and login test
Add byebug to Gemfile. Add json parser assert to integration test.
add test document do define actions we shoule have and how we test them.
Merge branch 'dev' into hbzhou

Conflicts:
	app/controllers/sessions_controller.rb
Merge branch 'dev' into hbzhou

Conflicts:
	app/controllers/sessions_controller.rb
fix routes error.
create user session test file. update test_arch doc.
add user signin/signup session integration test. signout is still not
work.
Merge branch 'hbzhou' into dev
Merge branch 'dev' of github.com:/us4us/seed into dev