Make CEL behavior conform to the documentation

This modifies the behavior of the CEL engine to conform to documented
behavior for Asterisk 12 as defined on the wiki
https://wiki.asterisk.org/wiki/display/AST/Asterisk+12+CEL+Specification

The primary changes deal with removal of the peer field from function
calls since it is no longer directly relevant to the bridging system
and removal of the layer of CDR-like business logic that was providing
a partial emulation of Asterisk 11 CEL functionality. With this change,
there is no longer a distinction between "bridges" and "conferences"
and all participation changes are denoted with bridge enter and bridge
exit messages.

This updates the CEL unit tests to handle these changes and simplifies
some of the macros used in the process.

This also fixes a segfault when attempting to ref a configuration that
failed to load.

Review: https://reviewboard.asterisk.org/r/2788/
(issue ASTERISK-21567)


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@397431 f38db490-d61c-443f-a65b-d21fe96a405b
Made the abstract jitter buffer resync on some more control frames.

Resync the abstract jitter buffer on the following additional control
frames:
AST_CONTROL_HOLD
AST_CONTROL_UNHOLD
AST_CONTROL_T38_PARAMETERS


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@397440 f38db490-d61c-443f-a65b-d21fe96a405b
Handle default body types for SIP event packages in res_pjsip_pubsub

Prior to this change, we would reject SUBSCRIBE requests that had no Accept
headers. Now event package handlers that handle the default type for the
event package indicate that they do so. Therefore, if we have a handler that
can handle the default type, we can allow SUBSCRIBEs for the handler's event
package that have no Accept headers.

(closes issue ASTERISK-22067)
reported by Mark Michelson

Review: https://reviewboard.asterisk.org/r/2774


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@397441 f38db490-d61c-443f-a65b-d21fe96a405b