Description of problem:
logwatch.conf is configured not to search archives by default.  In
fact the comments read:

# This usually will not do much if your range is set to just
# 'Yesterday' or 'Today'...

But the comment is not correct.
The setting does much on days when the logs get rotated (weekly).

Version-Release number of selected component (if applicable):
logwatch-5.1-4

How reproducible:
Always

Steps to Reproduce:
1. 4am Day 1: logwatch runs to process logs from Day 0 (yesterday)
2. 4am Day 1: logrotate rotates logfile to logfile.1, etc.
3. 4am Day 2: logwatch runs to process logs from Day 1 (yesterday)

Actual Results:
Anything before 4am on Day 1 isn't watched

Expected Results:
Logwatch should report on all log entries produced "yesterday."

Additional info:
I had an intrusion attempt that logwatch didn't report from
/var/log/secure because the attempt occured at 1:30am.  I began to
wonder why logwatch didn't report it.  (Nevertheless, I don't consider
this bug a security bug.)

Note that I am only recommending "Archives = Yes" in the default
config.  I am not recommending "Range = All" even slightly.

All RH and FC releases prior to FC3-test1 should be affected as well.