minor symfony#7304 update year in license template (xabbuh)

This PR was merged into the 2.7 branch.

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update year in license template

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2060178 update year in license template

Author: xabbuh

contributing/code/license.rst

@@ -16,7 +16,7 @@ According to `Wikipedia`_:
 The License
 -----------
 
-Copyright (c) 2004-2016 Fabien Potencier
+Copyright (c) 2004-2017 Fabien Potencier
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal