add fwd and rev message scroll keys as default and return to same message when doing a message forward

add fwd and rev message scroll keys as default and return to same message when doing a message forward

- New struct for matchs
- On calls originated from an FXS branch, the Endpoint searches for a valid extension (digits sent) after the DTMF '#' or after the timeout (option fxs-digit-timeout). That search is done in the context defined in section <fxs-options>, or if no context configured, the search is done in context defined in context-fxs.
- Added "dialplan" configuration: Name of the dialplan module in use
(default XML)
- Group context enabled. If set, the search for a valid extension is done only in that context.
- Updated documentation

switch_rtp: Show the UUID of the session in the log when sending RFC2833 DTMF packet and when receiving a RTP DTMF