Update LICENSE year & include in recipe

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2017 the contributors of the "Python for .NET" project
+Copyright (c) 2006-2017 the contributors of the "Python for .NET" project
 
 Permission is hereby granted, free of charge, to any person obtaining a
 copy of this software and associated documentation files (the "Software"),

conda.recipe/meta.yaml

@@ -26,3 +26,4 @@ test:
 about:
   home: https://github.com/pythonnet/pythonnet
   license: MIT
+  license_file: LICENSE