registration 7.x-1.6

This release fixes an issue with the upgrade path to the 7.x-1.5 release that was causing fatal errors for some users. It contains one patch:

• #2546836 by heddn: Fatal error: Class 'RegistrationTypeController' not found

7.x-1.5 included a fix for a minor security issue where, under certain configuration conditions, anonymous users who knew the usernames of site users could discover whether those users were registered for events. This only effects sites that gave anonymous users the "Event: Register other accounts" permission. After updating to this release, the permissions have been slightly restructured, and site administrators should revisit their registration permissions to ensure they are properly configured.