Update license copyright year

LICENSE

@@ -1,5 +1,5 @@
 Copyright (c) 2013 Thiago de Arruda
-Copyright (c) 2016-2019 Eric Freese
+Copyright (c) 2016-2021 Eric Freese
 
 Permission is hereby granted, free of charge, to any person
 obtaining a copy of this software and associated documentation

zsh-autosuggestions.zsh

@@ -2,7 +2,7 @@
 # https://github.com/zsh-users/zsh-autosuggestions
 # v0.6.4
 # Copyright (c) 2013 Thiago de Arruda
-# Copyright (c) 2016-2019 Eric Freese
+# Copyright (c) 2016-2021 Eric Freese
 # 
 # Permission is hereby granted, free of charge, to any person
 # obtaining a copy of this software and associated documentation