Install gogoprotobuf into $PWD/gopath just like all the other Go packages
Goprotobuf "option go_package" does not seem to work, avoid it

It would need to import a *.proto that defines that option, but the
source tree does not seem to provide one.
Regenerate goprotobuf log.pb.go; unavoidable noise from previous commit
Make gogoprotobuf find it's import files
Don't rely on {foo,bar} bashism in Makefile