scheduler: Clear the content of obsolete files periodically

Clear the content of log files every one hour to avoid disk being full.

BUG=chromium:747841
TEST=check content of /www/logs/lighttpd.error.log is cleared
periodically.

Change-Id: I97ca2b5102b1efefdbd988d68fb7092cb8bc96be
Reviewed-on: https://chromium-review.googlesource.com/608733
Commit-Ready: Cheng-Yi Chiang <cychiang@chromium.org>
Tested-by: Cheng-Yi Chiang <cychiang@chromium.org>
Reviewed-by: Shyh-In Hwang <josephsih@chromium.org>
2 files changed