Issue #2776751 by dpi: Harmonise APIs for Entity\SmsMessageInterface and...

Issue #2776751 by dpi: Harmonise APIs for Entity\SmsMessageInterface and Message\SmsMessageInterface

Removed provider::queueIn()
Removed provider::queueOut()
Allowing standard messages on queue(), not just entity.
Promoted set/getDirection from message entity to common method.
Promoted direction tests to message trait, which enables coverage on both message classes.

Fixed dpi/smsframework#42