Feature Request: Keep submodules and symlink path

[oliverhulett]

Instead of cloning a submodule each time, copying the files and then removing the cloned submodule, the update would be quicker and working with changes that span multiple repositories would be easier if quack kept the cloned submodules and linked into them instead of copying. I'm suggesting we implement this as a command line option and/or an optional field in the yaml file or module config.