Fix ip_to_cron parameter default
Fix ip_to_cron parameter default

A runinterval of 30 seconds must be a bug surely?  Cron can't work with
anything less than whole minutes.  I imagine the default was supposed to
be 30 *minutes* (1800 seconds), to match the default puppet runinterval.

voxpupuli/puppet-extlib,duritong/puppet-extlib,puppet-community/puppet-extlib