Add reference to examples for files and custom, too make it more obious

that you're required to read on... (hello xrobau)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@13323 65c4cc65-6c06-0410-ace0-fbb531ad65f3

configs/musiconhold.conf.sample

@@ -11,8 +11,9 @@ directory=/var/lib/asterisk/mohmp3
 ; mp3 		-- loud
 ; mp3nb		-- unbuffered
 ; quietmp3nb	-- quiet unbuffered
-; custom	-- run a custom application 
+; custom	-- run a custom application (See examples below)
-; files		-- read files from a directory in any Asterisk supported format
+; files		-- read files from a directory in any Asterisk supported 
+;		   media format. (See examples below)
 
 ;[manual]
 ;mode=custom