added new sort by reversed base url

[pschwede]

Attention, this is not tested yet. I need to install the Addon SDK as soon as I am home. edit: It is tested now.

eg. these urls where previously sorted like this:

• "http://banana.com/spam"
• "http://web2.salami.org/foobar"
• "http://www.banana.com/spam?with=eggs"
• "http://www.salami.org/spam"

Mixing "banana" and "salami" because of subdomains was not useful. Now take this:

• "http://banana.com/spam"
• "http://www.banana.com/spam?with=eggs"
• "http://web2.salami.org/foobar"
• "http://www.salami.org/spam"

That looks better, doesn't it? It's what I call the new sort by reversed base url.