StackOverflow OAuth2 Strategy for OmniAuth 1.0.
All credit due to Mark Dodwell, this repository is a hacked up copy of his Facebook OAuth2 Strategy. When I get a chance I will put all the specs back in and everything, promise!
Configuration is a little different to other Omniauth strategies, Stack Exchange use an app id as well, configure it like this (in the Devise initialiser);
config.omniauth :stackoverflow, '<client_id>', '<oauth secret>', :scope => 'no_expiry', :oauth_key => '<oauth key>'