Add note about configuring list_items on a single line.

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Merged revisions 422855 from http://svn.asterisk.org/svn/asterisk/branches/13


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@422856 65c4cc65-6c06-0410-ace0-fbb531ad65f3

configs/samples/pjsip.conf.sample

@@ -456,7 +456,9 @@
 ;way these are interpreted is event-package specific. For instance, with presence
 ;list_items, hints in the dialplan are looked up. With message-summary list_items,
 ;mailboxes are looked up using your installed voicemail provider (app_voicemail
-;by default).
+;by default). Note that in the above example, the list_item options were given
+;one per line. However, it is also permissible to provide multiple list_item
+;options on a single line (e.g. list_item = alice,bob,carol).
 
 ;In addition to the options presented in the above configuration, there are two
 ;more configuration options that can be set.