* because it is not referentially transparent; normally we reserved parens for
side-effecting code but given how people thoughtlessly close over it we revised
that that decision for sender
* caller can still omit parens
- removed retry-window and related settings
- removed gate-invalid-addresses-for
- gate is now mandatory
- remoting has a dedicated dispatcher by default
- updated tests to work with changed timings
- added doc section for association lifecycle
