[php] cleanup php session files

# Every 30 minutes, not on the hour<br>
# Grabs maxlifetime directly from \`php -i\`<br>
# doesn't care if /var/lib/php5 exists, errs go to /dev/null<br>

09,39 * * * *   find /var/lib/php5/ -type f -cmin +$(echo "\`php -i|grep -i session.gc_maxlifetime|cut -d' ' -f3\` / 60" | bc) -exec rm -f {} \\; >/dev/null 2>&1

The Breakdown: Only files: find /var/lib/php5/ -type f
Older than minutes: -cmin
Get php settings: $(echo "`php -i|grep -i session.gc_maxlifetime
Do the math: |cut -d' ' -f3` / 60" | bc)
RM matching files: -exec rm -f {} \;