Messages, queues, and tags

Hello,

I’ve been following the changes Josh is making to the GR messaging
system.
I am not sure that a gr_tag is a good fit for a generic message. For
example, the ‘offset’ may not be relevant to many messages.

We’ve been using tags very extensively in our designs and they are great
but serve a very different purpose than messages should. Perhaps a
better
idea is to define a standard message header?

Eugene