Current definition of python plugins is that a a python plugin defines a group (a language or generic). This makes it hard to make small python plugins which adds a check to an existing group. Problem becomes visible when splitting generic, when trying to package a check separately or when adding a personal python plugin.

Current work-around is that review_helper presents some known groups under a common header. This is less than ideal since it means that review_helper must know the groups, making true plugins impossible.

Quick and maybe not so dirty fix: some name magic in the group name. Lets say we have a 'Generic' group'. We can then interpret the group names Generic.setup and Generic.should as subgroups which should be treated as part of Generic.