RSS feed contains the host of the requested server

Imagine running jetty standalone on localhost:8080, having a proxy before. The RSS feed gets the scheme, name, port
from the RSSServletRequest.

<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:taxo="http://purl.org/rss/1.0/modules/taxonomy/" version="2.0">
<channel>
<title>New Artifacts in Repository 'internal'</title>
<link>https://localhost:8080/archiva/feeds/internal</link>

Maybe having a configuration setting is an option, where the URL base for thinks like "WebDavURL", "RSS base URL" etc. can be set
manually instead of guessing them in different ways (ContextUtils.java, req.getBaseUrl( ), etc.)