Make the SAL/Kafka producers shut down gracefully for SIGTERM (and SIGINT).
Pull request: https://github.com/lsst-ts/ts_salkafka/pull/15
Merged to develop and master and released as v1.4.0
I also deleted all 1.4.0 pre-release tags except the most recent: v1.4.0.rc.6, in case it is still being used anywhere. I will delete that one later.
I also deleted the v1.4.0.rc.6 tag with permission from Tiago Ribeiro