FreeSWITCH-FS-7269

Skinny: rewrite of the skinny state machine

- for incoming calls, go CS_ROUTING only when number is dialed.
  CS_HIBERNATE before
- start media when both side have answered

Also:
- send tone for UNALLOCATED_NUMBER and USER_BUSY
- if channel variables are not sufficent to set call info, ask the
  partner channel