Use DOKKU_ROOT instead of HOME.

HOME is not consistent if dokku is ran e.g. as root (for setup).
The DOKKU_ROOT variable will also make it possible to have the repositories stored in an arbitrary location (works-ish right now)

plugins/nginx-vhosts/install

@@ -13,10 +13,10 @@ if ! grep -q dokku-nginx-reload "/etc/sudoers"; then
   rm /tmp/sudoers.new
 fi
 
-echo "include $HOME/*/nginx.conf;" > /etc/nginx/conf.d/dokku.conf
+echo "include $DOKKU_ROOT/*/nginx.conf;" > /etc/nginx/conf.d/dokku.conf
 
 sed -i 's/# server_names_hash_bucket_size/server_names_hash_bucket_size/' /etc/nginx/nginx.conf
 
-[[ $(dig +short $HOSTNAME) ]] && echo $HOSTNAME > $HOME/VHOST
+[[ $(dig +short $HOSTNAME) ]] && echo $HOSTNAME > $DOKKU_ROOT/VHOST
 
 /etc/init.d/nginx start