Squid: Avoid cycle between java packages

https://trello.com/c/A0rrIWb0

Resolved packages dependency cycle in MOTECH SMS API
* Moved SmsAuditServiceImpl and SmsServiceImpl to service.impl

Change-Id: Ic2fd3eb327215e711952ef5db03d8e2e0bb49e1f
Merge "Squid: Avoid cycle between java packages"