We do not want to rely solely on one pattern for detecting login
attempts. This change creates a simple static list with patterns that
have a weight. If the pattern matches, the weight is added to the IP
score total. If the score total exceeds the max, the IP is blocked.
Previously we blocked on count=3, now we block when score=1.0.
The weight from the standard invalid user login is now dropped to
0.4 to have the same effect.
The `threshold` parameter is now therefore obsolete, and if found in
the config file, it will be ignored.