Why/How I did:
Make sure first error syslog is triggered based on FAULT TOLERANCE condition.
Added support of repeat clause with alert action. This is used as trigger
for generation of periodic syslog error messages if error is persistent
Updated the monit conf files with repeat every x cycles for the alert action
We want to let Monit to unmonitor the processes in containers which are disabled in `FEATURE` table such that
Monit will not generate false alerting messages into the syslog.
- Backport of https://github.com/Azure/sonic-buildimage/pull/5153 to the 201911 branch
Signed-off-by: Yong Zhao <yozhao@microsoft.com>