Update bridge_channel refactorings; export bridge_ symbol

git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@395295 f38db490-d61c-443f-a65b-d21fe96a405b
Export exports.in as well

Because is is rather needed.

git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@395298 f38db490-d61c-443f-a65b-d21fe96a405b