Advanced use cases

Note: This includes the changes from my previous pull request.

This contains two pretty major behaviour changes amongst some other minor ones:
Firstly, project references can now also be converted to NuGet references.
Secondly, versions numbers are now included by default - because I wanted to add the option, and making it the opposite of the NuGet default was too confusing.

I'm happy to rejig the branch if you don't want to take all of the changes. It's essentially the list of things I needed to make it useful for a big solution I was working on, just thought I might as well push them upstream.