Allow for the execution of an AGI to the caller's channel right before they...

 Allow for the execution of an AGI to the caller's channel right before they get bridged with the queue member that is going to take their call. Add the option to set a MEMBERINTERFACE variable on the caller's channel that will contain the interface of the queue member that is going to/did take the call. #6843 



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@25056 65c4cc65-6c06-0410-ace0-fbb531ad65f3