Adding Perfdata

Good plugin, I added Perfdata for NagiosGraph replacing the final 3 IF by this code:

if [[ “$percent” -le $critical ]]; then
echo “CRITICAL – $free MB ($percent%) Free Memory | total=${total}MB used=${used}MB”
exit $STATE_CRITICAL
elif [[ “$percent” -le $warning ]]; then
echo “WARNING – $free MB ($percent%) Free Memory | total=${total}MB used=${used}MBº”
exit $STATE_WARNING
elif [[ “$percent” -gt $warning ]]; then
echo “OK – $free MB ($percent%) Free Memory | total=${total}MB used=${used}MB”
exit $STATE_OK
fi