This commit prevents cdr records with AST_CDR_FLAG_ANSLOCKED and AST_CDR_FLAG_LOCKED...

This commit prevents cdr records with AST_CDR_FLAG_ANSLOCKED and AST_CDR_FLAG_LOCKED from being updated in certain cases.

This is accomplished by adding two functions to update the answer time and disposition of calls that checks for the proper lock flags.  These functions are used in the ast_bridge_call() function so that ForkCDR(A) calls are respected.

This patch also modifies the way ast_bridge_call() chooses the cdr record to base the bridged_cdr on.  Previously the first unlocked cdr record would be chosen, now instead the first cdr record is chosen and forked cdr records are moved to the bridge_cdr.  This allows the original cdr record and any forked cdr records to be properly updated with answer and end times.

(closes issue #13797)
Reported by: sh0t
Tested by: sh0t

(closes issue #14744)
Reported by: deepesh

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@195881 65c4cc65-6c06-0410-ace0-fbb531ad65f3