The Confluence installer appears to not detect modifications to server.xml

For our deployment of Confluence Standalone on Linux, we have it running behind a proxy server out of a subdirectory on our domain. As such, we have a modified server.xml that changes the port, sets the proxy domain name and port, and sets the root directory.

Upgrading Confluence via the installer catches other modified or unrecognized files, but does not appear to recognize changes to server.xml and, as such, we are forced to manually updated server.xml each time.