When a conductor program is interrupted via ctrl-c or equivalent it is much nicer log that that has happened and to reraise that exception. This also slightly tweaks the 99 bottles song to make it even better, by having more pieces/tasks, which makes it possible to kill the program during each task and see how the resumption works when a flow is composed of segments. Change-Id: I5d242eba9a043ef96646ba74ea5928daa0691ed0