I missed a spot where I referenced the nested_paths as nested_pathnams
after I renamed the variable. Now, Msf::ModuleManager#add_module_paths
has rspec tests.
Rspec can be invoked with `rake` as the default task or `rake spec`
explicitly.
I changed RuntimeError to ArgumentError since that error was more
specific to having a bad argument error. I adding missing dependencies
to the Gemfile and a require to msf/core/db_manager.rb where it errored
out trying to access Msf::Config when I just did require 'msf/core' in
the spec.
[Fixes#36737359]
Refactor Msf::ModuleManager into concerns so its easier to understand and
duplicate code can be made DRY. The refactoring also ensures that when
loading from directories, Fastlibs, or reloading, the wrapper module will
always be named so that activesupport/dependencies will function.
