This means the writing to a WriteFlusher will flush in the same places
as it would if the broadcaster wasn't sitting in front of it.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
- Rename to Broadcaster
- Document exported types
- Change Wait function to just wait. Writing a message to the writer and
adding the writer to the observers list are now handled by separate
function calls.
- Avoid importing logrus (the condition where it was used should never
happen, anyway).
- Make writes non-blocking
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>