Support pointers to structs in the go-runtime

[alecthomas]

Currently every time must be a value type, not a pointer. This is annoying.

[alecthomas]

To be honest, I'm not sure this is a good idea, as requiring values prevents an entire class of errors and reduces confusion. What I mean by this is that if you have a struct like this:

type MyRequest struct {
  Name string
  Address *Address
}

Does a pointer indicate optional, or just that we want to use a pointer?

It is somewhat annoying having to type out in function return values, that's for sure. Another option could be to only allow pointers in request/response structs.