Exclude some addresses from anonymization

[tobiasherp]

I currently use anonip to change the last byte (I have IP4 addresses only, for now) in the logs, changing e.g. 123.123.123.123 to 123.123.123.0 (the default behaviour).

Now I'd like to except my "own" addresses from log analyzing. Let's say the external IP addresses from our company are 123.123.123.122 and 123.123.123.123 (or 123.123.123.122/31). I'd like to leave these addresses intact for e.g. AWStats to recognize them as "internal" and ignore them (SkipHosts configuration setting).

This is similar to (but much simpler than) the --skip-private option which allows to except Special-Use Addresses from masking.

Currently I'd need to tell AWStats to ignore 123.123.123.0 altogether, missing e.g. all requests from 123.123.123.128/25. Or do very complicated things. It shouldn't be necessary to parse the logs for particular IP addresses more than once, right?

I propose a --skip option which could be used independently from --skip-private; it could add to a list or take more than one value.