- Added optional state parameter
- Added redirect_uri override setting when it's set in the the provider config to prevent redirect uri mismatch errors

With the redirect_uri setting in the config and the state parameter it's possible to create a single entry point for all Google authentification requests.
Added proper indenting
Changed spaces to tabs
Changed spaces to tabs
Merge pull request #196 from wvdweij/master

close #194 - Added optional state parameter and redirect uri override in Google Provider