Add debian support with 1.8

CopySpec completely changed in 1.8, separating out CopySpec and CopyActions. This pull request aligns with 1.8, and won't work with anything earlier. There's some other changes to make it easier for me to work with, like removing nexus and bumping the version. I can see what is required to get those back if needed. (Though I don't believe in putting publishing code into the build, it's factor specific to the user, and they can injected via -I.)