r366547 introduced a change to the directmedia ACL for chan_sip which
modified the behavior significantly. Prior to the patch, this option would
bridge peers with directmedia if a peer's IP address matched its own
directmedia ACL. After that patch, the peer would check the bridged peer's
ACL instead. This change has been present since 1.8.14.0. That patched failed
to document the change in Upgrade.txt, so this patch adds mention of that
change to UPGRADE.txt (UPGRADE-1.8.txt in newer branches)

(issue AST-876)
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Merged revisions 372471 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 372472 from http://svn.asterisk.org/svn/asterisk/branches/10
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Merged revisions 372473 from http://svn.asterisk.org/svn/asterisk/branches/11


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@372474 65c4cc65-6c06-0410-ace0-fbb531ad65f3