Add SMS event to Secure Messaging (#6594)
* Add SMS event to Secure Messaging
- support sending SMS to patient from messaging.
* prevent listener if module not enabled
* - quite PHP session is already started notice which does a stack trace 18 deep!
* - php error/warning fixes
- ensure session is closed to write before a new write
* - opps wrong file version previous commit
* - remove init sms api class on construct in notification listener.
* - add new environment debug variable to turn off dated reminders and background service from running.
* Revert "- add new environment debug variable to turn off dated reminders and background service from running."
This reverts commit
289d3eb92c4e2c6eaf1c08ed1040e701c08bf136.