Update copyright year (#1832)

Update copyright year to 2020 and change to multi-year format.

LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2016 Junegunn Choi
+Copyright (c) 2013-2020 Junegunn Choi
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README-VIM.md

@@ -338,4 +338,4 @@ endif
 
 The MIT License (MIT)
 
-Copyright (c) 2019 Junegunn Choi
+Copyright (c) 2013-2020 Junegunn Choi

README.md

@@ -602,4 +602,4 @@ https://github.com/junegunn/fzf/wiki/Related-projects
 
 The MIT License (MIT)
 
-Copyright (c) 2019 Junegunn Choi
+Copyright (c) 2013-2020 Junegunn Choi

doc/fzf.txt

@@ -338,7 +338,7 @@ LICENSE                                                            *fzf-license*
 
 The MIT License (MIT)
 
-Copyright (c) 2019 Junegunn Choi
+Copyright (c) 2013-2020 Junegunn Choi
 
 ==============================================================================
 vim:tw=78:sw=2:ts=2:ft=help:norl:nowrap:

man/man1/fzf-tmux.1

@@ -1,7 +1,7 @@
 .ig
 The MIT License (MIT)
 
-Copyright (c) 2019 Junegunn Choi
+Copyright (c) 2013-2020 Junegunn Choi
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

man/man1/fzf.1

@@ -1,7 +1,7 @@
 .ig
 The MIT License (MIT)
 
-Copyright (c) 2019 Junegunn Choi
+Copyright (c) 2013-2020 Junegunn Choi
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

src/LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2017 Junegunn Choi
+Copyright (c) 2013-2020 Junegunn Choi
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal