hgweb: support alternate logo url Clicking on the logo image/text in the hgweb interface brings the user to the Mercurial project page. The majority of users expect that this would bring them to the top level index. I have added a new template variable named `logourl' which allows an administrator to change this behavior. To stay compatible with existing behavior, `logourl' will default to http://mercurial.selenic.com/. This change is very useful in large installations where jumping to the index is common.