Remove unused Msf::ModuleSet#derive_module_class

MSP-9228

Method was created before Metasploit::Framework::Module::Class::Load was
designed.
Don't allow Msf::ModuleManager#module_types to be variable

MSP-9228

The module cache assumes that all module types should be loaded, so the
module manager having types has no effect.
Remove Msf::Framework#module_types

MSP-9228

Propagate removal of Msf::ModuleManager#module_types.