use webapp2 latest (2.5.2)
use sessions
add config for webapp2
copy AuthHandler from simpleauth

https://github.com/crhym3/simpleauth/blob/ed342a572b357bacd08ef4cea9fdee43716b3ce8/example/handlers.py
Oct 29, 2013 ed342a572b357bacd08ef4cea9fdee43716b3ce8
remove white spaces
remove comments
replace info logging level with debug
import fix
fix version of simpleauth
use OAuth via simpleauth
add tests for sessions
refactor
update for secrets
set session_max_age to webapp2_extras.sessions
refactor
back to the original url when sign in
add tests for OAuth
remove utils.OAuth._to_user_model_attrs
fix tests on offline
fix offline tests