(PDB-3067) Log at debug when command is enqueued
(PDB-3067) Log at debug when command is enqueued

When a command is placed on the queue, log its ID, command name, and
certname at the debug level, similar to the logging after the command is
processed.

rbrw/puppetdb,mullr/puppetdb,puppetlabs/puppetdb,mullr/puppetdb,mullr/puppetdb,puppetlabs/puppetdb,waynr/puppetdb,puppetlabs/puppetdb,senior/puppetdb,puppetlabs/puppetdb,rbrw/puppetdb,waynr/puppetdb,rbrw/puppetdb,mullr/puppetdb,senior/puppetdb,puppetlabs/puppetdb,mullr/puppetdb,waynr/puppetdb,rbrw/puppetdb,senior/puppetdb,waynr/puppetdb,senior/puppetdb,rbrw/puppetdb