Allow for instant canceling
Allow for instant canceling

lava-master listen for events from lava-publisher. When a testJob is canceled,
and event is generated and published by lava-publisher.
The event is received by lava-master that will try to cancel the corresponding
job.

Change-Id: I7d7255fcf661480cbcde26e6c859583297844d8d

Linaro/lava-server,Linaro/lava-server,Linaro/lava-server,Linaro/lava-server