remove dupe author

docs/announce/2015.12.md

@@ -61,7 +61,7 @@ Masahiro Honma, Yoshikuni Jujo, Zohar Kelrich, Moritz Lenz, Carl Masak,
 quietfanatic
 
 Martin Berends, diakopter, Solomon Foster, Tobias Leich, Paweł Murias,
-Stefan O'Rear, pmurias, Daniel Ruoso, Larry Wall
+Stefan O'Rear, Daniel Ruoso, Larry Wall
 
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