add update site to default properties - can still be overidden by command line option -Dupdate.site=www.foo.com
add update site to default properties - can still be overidden by command line option -Dupdate.site=www.foo.com


git-svn-id: e057f57e93a604d3b43d277ae69bde5ebf332112@982531 13f79535-47bb-0310-9956-ffa450edef68

apache/felix-dev,apache/felix-dev,apache/felix-dev,apache/felix-dev