add queue_dtmf application, takes one param, a string of dtmf that will be queued to send from the channel.  You could use this in the dialplan before a bridge to queue up dtmf to be sent to the other channel for example if you need to dial digits after answer for an fxo ata device.

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@4085 d0543943-73ff-0310-b7d9-9358b9ac24b2