Flatten task namespaces

Avoids weirdness when a task module is imported from another
module.

E.g., if the apple module imports the banana module, you would
previously end up with a task name 'apple.banana.task'. Now this
loads as 'banana.task' as expected.
Support config file format for hivemindrc
Override command defaults via config file
Add hokey config file namespace filtering
Fix backwards compat for config