Make newsyslog utility run only once a day (at midnight) and not every hour.

Even though newsyslog has if conds which only turn the particular logfiles
when above conds are met, each time newsyslog is run from the cron
(which was every hour) syslog-ng prints a noisy message.

Also, as per Josh and Xin if you want a command to run roughly after a
month but on the same day, do it after 35 days instead of 30.
So changed the boot pool scrub to follow above logic.