Automating version number in protobuf marshalling

(I had this laying around and figured I should submit it before I forgot about it.. ;) )

The downside of the code is that the replacer-plugin will automatically modify the code after a release. However, that's also kind of the upside. 

Because the `-SNAPSHOT` of the version isn't used (parse-version), the code replacement won't happen until *after* a release.