Update to 4.0

Author: tianon

Dockerfile

@@ -36,7 +36,7 @@ RUN rm -rf /var/www/html && mkdir /var/www/html
 VOLUME /var/www/html
 WORKDIR /var/www/html
 
-ENV WORDPRESS_VERSION 3.9.2
+ENV WORDPRESS_VERSION 4.0
 
 # upstream tarballs include ./wordpress/ so this gives us /usr/src/wordpress
 RUN curl -SL http://wordpress.org/wordpress-$WORDPRESS_VERSION.tar.gz | tar -xzC /usr/src/