Multi-threaded deploy at end

[Jeffrey E Care]

We have several medium-to-large multi-module builds. We use deploy at end 
and I've noticed that it's taking a long time to run the deploys. I dug 
into the deploy plugin & noticed that for deploy at end the deployments 
are run serially. Has there been any thought to using multiple threads for 
this use case? Would you be open to a contribution implementing this?