New optional user interface for populating the LocalUserDetailsManagerImpl instance provided in the 'local-users' profile. The default configuration will still use the existing LocalUserDetailsAttributesMapper.Default implementation.

To switch to the new loader, set the 'edu.wisc.uwss.local.userDetailsLoader.enabled' Environment property to true. The default resource loaded is edu/wisc/uwss/local/local-users.json (classpath), to change that location set the 'edu.wisc.uwss.local.userDetailsLoader.resource' Environment property to a valid Spring Resource expression ('classpath:', 'file:', etc).