Loading plugin breaks configuration for all plugins.

[sberl]

I attempted to install this plugin. Once installed, going to the plugin config page in the server admin interface displays only a "Something went wrong" message. None of the plugins can be configured at this point.
This plugin should be updated to conform to the expectations of the plugin loading infrastructure of the recent server versions. I believe it is failing because it is missing the plugin.schema object.

There is a related issue for the server itself that this situation should be handed more gracefully.