Can't unload modules when companion submodules are dependent on them

[cooper]

For example, Ban::TS6 is loaded and unloaded with TS6::Base. But you can't MODUNLOAD Ban::TS6 independently of Ban because it is a submodule. When you try to unload TS6::Base, it says that Ban::TS6 depends on it. The only way to get around this currently is to unload Ban, which consequently unloads Ban::TS6, and then unload TS6::Base.

Basically, when attempting to unload a module with dependents that are companions to it, unload the dependents before unloading the requested module and do not raise an error.