If this optional parameter is set to non-zero, it specifies
the time period in seconds that ClientListLDAP will refresh the client
list by rereading the database. If set to 0, then ClientListLDAP will only
read the client list from the database at startup and on SIGHUP. Defaults
to 0. The % formats are permitted.
# Reread the client list every hour
RefreshPeriod 3600