Make a more generic "outboundSender"/dispatcher

[kristinapathak]

caduceus/outboundSender.go

Line 455 in 76e8eab

func (obs *CaduceusOutboundSender) dispatcher() {

The dispatcher in the outbound sender is similar to what talaria needs to send events out and what mimisbrunnr will need to send out events. We can take out of the outboundSender the pieces that are more general and put them in their own library, for all three services to use.

The details of this haven't really been investigated.