Rename `conn_rec->remote_ip` to `conn_rec->client_ip`

Apache v2.4 has changed the conn_rec record structure (see, http://httpd.apache.org/docs/2.4/developer/new_api_2_4.html)
Ensure that the Apache logging is also v2.4 compatible
Detect if the Apache `conn_rec` structure uses `client_ip` and uses it accordingly.
Fallback is the original `conn_rec->remote_ip`.
Merge pull request #5 from scottwallacesh/apache24

Apache24