use purge to get rid of apache

scripts/web.sh

 # HTTP: Turn on a web server serving static files
 #################################################
 
-apt-get remove -q -y apache2
+# Remove Apache before installing Nginx. Apache may leave
+# some unwanted configuration files around (e.g. a ufw
+# application config), so purge the packages.
+apt-get purge -q -y apache2 apache2.2-common
+
 apt-get install -q -y nginx php5-cgi
 
 rm -f /etc/nginx/sites-enabled/default