Reduce the amount of plugin definitions being created

Problem/Motivation

The amount of plugin definitions always multiplies with the amount of existing content entity bundles. That may result to a lot of definitions. The amount needs to be reduced so that the overhead of plugin definitions is not too high.

Steps to reproduce

Proposed resolution

The task, subject and qualifier plugin managers can be optimized, so that they recieve additional arguments when loading definitions. With these arguments, plugin definitions may be dynamically build up on request:

• The deriver is not creating one definition for each combination of subject type and bundle, instead the plugin definition declares a list of allowed types and bundles (all at once).
• Then, when requesting plugin definitions for a specific type and bundle combination, possible combinations that match up with the arguments are being build up.

Remaining tasks

User interface changes

API changes

Data model changes