Set provider_ignores_state

Put.io does not transfer the state parameter as a CRSF protection
Merge pull request #1 from mxey/master

Make it work with omniauth-oauth >= 1.1.0

Put.io does not transfer the state parameter as a CRSF protection.

See this omniauth-oauth2 issue for context: https://github.com/intridea/omniauth-oauth2/pull/23