beam.Task: plumbing for a long running task
beam.Task: plumbing for a long running task

Signed-off-by: Solomon Hykes <510d74b69d9d43b60b6f6aa9d95e9f9c9497f815@docker.com>

beni55/libchan,wangtuanjie/libchan,dmcgowan/libchan,docker/libchan