Update credits.

CREDITS.md

@@ -32,8 +32,8 @@ Contributors to Magnum library
 *   [@wivlaro](https://github.com/wivlaro) -- numerous bug reports, Mac OS X
     fixes, feature improvements
 *   Jonathan Hale ([@Squareys](https://github.com/Squareys)) -- Audio library
-    enhancements, GlfwApplication implementation, bug reports, documentation
-    improvements
+    enhancements, GlfwApplication implementation, frustum culling, bug reports,
+    documentation improvements
 *   Gerhard de Clercq -- Windows RT (Store/Phone) port
 *   Ashwin Ravichandran ([@](ashrko619)[https://github.com/ashrko619]) --
     Bézier curve implementation

src/Magnum/Math/Geometry/Distance.h

@@ -5,6 +5,7 @@
 
     Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016
               Vladimír Vondruš <mosra@centrum.cz>
+    Copyright © 2016 Jonathan Hale <squareys@googlemail.com>
 
     Permission is hereby granted, free of charge, to any person obtaining a
     copy of this software and associated documentation files (the "Software"),

src/Magnum/Math/Geometry/Intersection.h

@@ -5,6 +5,7 @@
 
     Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016
               Vladimír Vondruš <mosra@centrum.cz>
+    Copyright © 2016 Jonathan Hale <squareys@googlemail.com>
 
     Permission is hereby granted, free of charge, to any person obtaining a
     copy of this software and associated documentation files (the "Software"),

src/Magnum/Math/Geometry/Test/DistanceTest.cpp

@@ -3,6 +3,7 @@
 
     Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016
               Vladimír Vondruš <mosra@centrum.cz>
+    Copyright © 2016 Jonathan Hale <squareys@googlemail.com>
 
     Permission is hereby granted, free of charge, to any person obtaining a
     copy of this software and associated documentation files (the "Software"),