pbx: Wait 1 second before playing a prompt

Add a wait of 1 second after answering and before playing a prompt.
Sometimes it takes a little bit of time to set up the audio path.
If you don't wait a bit, the caller will miss the beginning of the
prompt.

Change-Id: Ied25fd6d90638d938b0cd04562ad15de1e7d0426

modules/openstack_project/files/pbx/asterisk/extensions.conf

@@ -3,6 +3,7 @@
 [public]
 
 exten => s,1,Answer()
+    same => n,Wait(1)
     same => n,Set(RETRIES=3)
     same => n,Set(COUNT=0)
     same => n,While($[${COUNT} < ${RETRIES}])
@@ -23,6 +24,7 @@ exten => _6XXX,1,Answer()
 
 ; Easter egg -- spam on the keypad.
 exten => 7726,1,Answer()
+    same => n,Wait(1)
     same => n,Playback(spam)
     same => n,Hangup()