add spec file

[jonassvatos]

[ctubbsii]

My personal opinion (and I have found this strategy to be best in other open source projects), is that packaging specifications are best left to downstream packaging environments, rather than maintained within the upstream open source project. In my opinion, it is better for the upstream project to facilitate "buildability", and downstream (such as in a Linux distro) to do the actual packaging in accordance with whatever downstream packaging conventions exist (RPM guidelines in Fedora... Ubuntu DPKG conventions.... Homebrew recipes... Docker containers... or whatever the downstream scenario calls for).

Putting those packaging specifications in the upstream project is "scope creep", I think. That's just my personal opinion, though... I'm not the maintainer of DCP. They may decide otherwise.