syweb's default install assumes that:
  - web server is chrooted at /var/www
  - rrdtool is installed in the chroot
  - symux rrd files are kept in /var/www/symon/rrds/<host>/*.rrd

Customise /var/www/htdocs/syweb/setup.inc if these assumptions are
incorrect. rrdtool must also be copied into the chroot jail; for this,
see rrdtool's pkg-readme document.
