When node's manager or agent fail from error, it should cancel context and exit.
When node's manager or agent fail from error, it should cancel context and exit.

Signed-off-by: Dong Chen <252dc6b7229d6040aded2d6fd307bed15f92f3c6@docker.com>

elifa/swarmkit,allencloud/swarmkit,fate-grand-order/swarmkit,aaronlehmann/swarmkit,jlhawn/swarmkit,diogomonica/swarmkit,alyyousuf7/swarmkit,Noyan759/swarmkit,deljuven/swarmkit,yongtang/swarmkit,sungwonh/swarmkit,allencloud/swarmkit,fate-grand-order/swarmkit,dperny/swarmkit-1,cheyang/swarmkit,elifa/swarmkit,sungwonh/swarmkit,docker/swarmkit,RenaudWasTaken/swarmkit,jlhawn/swarmkit,docker/swarmkit,aaronlehmann/swarmkit,AliyunContainerService/swarmkit,deljuven/swarmkit,dperny/swarmkit-1,yongtang/swarmkit,cheyang/swarmkit,AliyunContainerService/swarmkit,Noyan759/swarmkit,diogomonica/swarmkit,alyyousuf7/swarmkit,RenaudWasTaken/swarmkit