Add drush command to generate config schema for wrapper plugins

Problem/Motivation

Some integration module (e.g. eca_tamper or eca_commerce) derive their condition or action plugins from other modules (e.g. tamper or commerce) where config schema for those derived plugins already exists.

ECA may add extra fields to the schema of each plugin, but the original schema should just be grabbed from the source plugin.

Proposed resolution

Add a ConfigSchemaCommands drush file to eca_development with a new command which receives the plugin prefix (e.g. eca_tamper_condition or eca_commerce_commerce) so that it can find all the wrapper plugins with that prefix.

It should then be able to find the original schema definition from the wrapped plugin and use that together with a default definition that needs to be added to all those plugins.