See README for information about gopkg.in
If you are to develop on a versioned branch, use gopkg.in.
go get -u -v -t gopkg.in/juju/charm.v2/...
gopkg.in names the local branch master. To submit a pull request, push to your github branch using a refspec which reflects the version tag you are using.
git push git@github.com:jrwren/charm +master:v2