v0.13.0

One route, one line. go doc -all against 0.12.0 leaves di untouched and
adds dihttp.Handle; nothing changes shape or behaviour, and an upgrade
cannot break a caller.

Added

• dihttp.Handle(method) makes an http.Handler that resolves a handler
  type from the request's scope and calls one of its methods, named by a
  method expression: mux.Handle("GET /users/{id}", dihttp.Handle((*Users).Show)).
  One type per resource with a method per route replaces a type, a
  registration and a closure per route. The type is Scoped when it needs
  the request and a plain singleton when it does not; Handle follows
  either. Nothing existing changes; an upgrade cannot break a caller.