remove the mailinglist still preferred note, roundup is much nicer even though

it still has some issues which lu_zero needs to deal with :)

Originally committed as revision 9877 to svn://svn.ffmpeg.org/ffmpeg/trunk

doc/issue_tracker.txt

 ffmpegs bug/patch/feature request tracker manual
 ================================================
 
-NOTE, this is a draft, it is not yet recommended to send real bugreports to the
-tracker but rather use the mailing lists.
-Though, if you are brave and do not mind that your bugreport might disappear or
-that you might be mailbombed due to a misconfiguration, you can surely try
-to enter a real bugreport.
+NOTE, this is a draft
 
 Overview:
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