LP#1684970 Translator compatible with mod_remoteip

LP#1684970 Translator compatible with mod_remoteip

Teach the OSRF Translator to request the IP address of the user agent
(e.g. web browser) instead of the IP address of the up stream client,
which may be a proxy, using the Apache 2.4 request_rec->useragent_ip
value.

http://httpd.apache.org/docs/2.4/developer/new_api_2_4.html

This make is possible for the translator to access the client IP with
Apache's mod_remoteip enabled and configured.

Includes sample config and install documentation.

Signed-off-by: Bill Erickson <berickxx@gmail.com>