Retain 90 days of EventLogging logs

Due to space restrictions on the place where EventLogging previously
wrote its logs, log retention has been dialed back from 90 to 45 days
2014-08-01. Since EventLogging now writes its logs to a mount with
more free space, we go back to retaining 90 days of logs.

Bug: 69029
Change-Id: I760972c2edeb45075e783002b454153263126d04