Improve space export to HTML - fix top menu links and more

I'm using the following statement (linnux) to export a public XWiki space to plain html (see http://www.computer42.org/xwiki-static/index.html)

curl "https://www.computer42.org/xwiki/bin/export/${space}/Page?format=html&pages=${space}%25">${tmpFile}

• This produce an Login link pointing back to the link used by the curl
  statement. Following this link you download the whole space whith an
  massive performance penality of the live xwiki instance.

At least this link should be fixed.

• If the export was done by an authenticated user (basic authentication), there is also a link to the user profile which should be suppressed.

• At the bottom you found "comments, ... "
  All these links here pointing back to the page itself and not the comments, attachments, ...
  This bogus part should either be removed or showing links to the live content.

• An additional nice feature would be an option to suppress the "panel".
  As you see in http://www.computer42.org/xwiki-static/index.html it is not useful in the exported space.

My use cases for html exported spaces:

• reduce load on "live" xwiki instance
• create "offline" documentation
  • In the example above the "sailing" content can be used without internet connection.
  • Providing non-public space as HTML content export. On of my clients use this to maintain offline documentation for an application installed on a special set of work stations.