Fix dispatcher tweaks to correctly set application folder during short-circuit loads.
- Added GDN_UserAuthenticationProvider.IsDefault.
- Added the /sso method that plugins can tie into.
Merge branch 'release/2.1b1' of github.com:vanillaforums/Garden into release/2.1b1
Loop until a valid controller is found.
Merge remote-tracking branch 'origin/master' into release/2.1b1
Fix activity model wall post notifications.