Add myself to AUTHORS

Author: yokonao

AUTHORS

@@ -81,6 +81,7 @@ Lunny Xiao <xiaolunwen at gmail.com>
 Luke Scott <luke at webconnex.com>
 Maciej Zimnoch <maciej.zimnoch at codilime.com>
 Michael Woolnough <michael.woolnough at gmail.com>
+Nao Yokotsuka <yokotukanao at gmail.com>
 Nathanial Murphy <nathanial.murphy at gmail.com>
 Nicola Peduzzi <thenikso at gmail.com>
 Oliver Bone <owbone at github.com>