* Short-circuit legacy network module prefix->action mapping
* Modified a non-short-circuit compound conditional in a legacy networking path that attempted to resolve an action for any module name containing `_`. The bug was always present, but the typical presentation (an ImportError) was ignored prior to 2.19.
* The legacy networking path should be deprecated and removed in 2.20- a module could still be run under the wrong action if one with a matching prefix is found.
* unit test fix
d6efb7db8a