app_queue: Add StateInterface to output of "queue show" and "QueueStatus"

This patch adds the state_interface of the queue member struct to the output
of "queue show" (CLI command) and "QueueStatus" (AMI action) when displaying
relevant queue member information.  For the AMI event message the variable
StateInterface has been added.

(closes issue ASTERISK-18071)
Review: https://reviewboard.asterisk.org/r/1300/
Patch-by: Jamuel Starkey


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@331000 65c4cc65-6c06-0410-ace0-fbb531ad65f3