[Piuparts-reports] Cron <piupartsm at pejacevic> rotate_master_logs

[Cron Daemon]

'buster-rcmd/master.log' -> 'buster-rcmd/master.20180716.log'
'stretch2buster/master.log' -> 'stretch2buster/master.20180716.log'
'wheezy2bpo2jessie/master.log' -> 'wheezy2bpo2jessie/master.20180716.log'