message: doc: Add reminder about async_trait weirdness
  Add reminder for more documentation around associated function
  handling with async_trait
diff: @@ -51,3 +51,7 @@ As hardware can disconnect, or send data unprovoked, or do other things we don't
  ## Future Queuing
  _TODO: Talk about how we shuttle futures around inside the library_
  +
  +## Getting Around Associated Functions Like new()
  +
  +_TODO: Talk about non-async constructor traits_
  