Update license year 2019 (#1692)

### Fix license of use, 
update 2019; 
Format ISO 8869-1;
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in Memoriam Guto Schiavon 
![guto-schiavon_bitcoin](https://user-images.githubusercontent.com/7637553/50562143-a7506f80-0cf8-11e9-9e58-bed4565c4715.jpg)
R.I.P pioneer and friend. 

#ripGUTO

Author: Everton Melo

LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright 2017-2018 Ethereum Foundation
+Copyright 2017-2019 Ethereum Foundation
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal