Add support to the bridging core for performing COLP updates when channels join a 2 party bridge.

(closes issue ASTERISK-21829)

Review: https://reviewboard.asterisk.org/r/2636/


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@394249 f38db490-d61c-443f-a65b-d21fe96a405b