Update Master (#314)

* Fix structlog dependency for app (#280)

* zipfile fix (#284)

* Fix bug 286 random token replacement (#287)

* Fix bug 286 random token replacement

* Change perdayvolume generator logic to get random token value replacement

* Versioning scheme (#278)

* [global] perDayVolume (#288)

* exclude global from perDayVolume assignment

* Address comment

* Fix security vulnerability issue (#289)

* Fix custom plugin stale docs (#290)

* Server fix (#293)

* Flag added

* server fix for count and env clean

* Fix bug 285 (#297)

* Add syslogAddHeader config directive (#296)

* Add syslog header to event in syslog mode

* timezone setting bugfix #249

* Using multiprocess pool to address the OOM issue (#301)

* Using multiprocess pool to address the OOM issue

* Fix test case fail

* Remove workerQueue unfinished tasks (#302)

* Bumped version to 6.5.2

* controller fix (#304)

* controller fix

* variable assignment fix (#306)

* add healthcheck endpoint and ping it every half an hour (#308)

* Fix security vulnerability issue reported by GitHub (#309)

* make controller also hit redis on healthcheck (#311)