Merge 5 fragile proto-bindings scripts into 1

Each of these scripts is basically identical, and all were too brittle.
Now they should be more resilient and easier to manage.  The script
still needs to be updated if we add new ones, which I do not love.

More cleanup to follow.

hack/lib/protoc.sh

@@ -72,7 +72,7 @@ function kube::protoc::format() {
 
   # Run gofmt to clean up the generated code.
   kube::golang::verify_go_version
-  gofmt -l -s -w "${package}/api.pb.go"
+  gofmt -s -w "${package}/api.pb.go"
 }
 
 # Compares the contents of $1 and $2