Setup different messages per flow

[pavsaund]

At the moment it's possible to send messages to seperate flows, but not possible to specify which types of message go to which flow.

Also it's not possible to add mutiple Flowdock-steps, so I can't add seperate configs per flow.

[anttipitkanen]

Multiple flow notification configurations would be pretty nice, let's see if we have the time to prototype that in the near future.