Grouper custom provisioner

Summary

There are three ways to implement a custom provisioner:

1. GSH template provisioner: write the provisioning implementation in a "provisioning" GSH template

2. Generic provisioner: only has a DAO class configured in Grouper

3. Custom provisioner: an institution can implement code and configuration to have a provisioner that is similar to a Grouper built-in provisioner

Generally a provisioner in the framework (built-in or custom) will have a first class provisioner implementation.  i.e. you see it in the drop down, it has specific configuration and validation etc.

However, if you want to implement a custom generic provisioner and not write all the classes and configs to make that happen, you can use the generic provisioner.  Just implement a DAO class and register it in the provisioner.  All the configs specific to this provisioner should live elsewhere in the configuration, not with the provisioner configuration or external system.