Using first available port

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In previous versions of Cassini it was possible to specify the listening port  
as "0" and the first available local port would be assigned to it (which then 
was accessible via URL property)

That feature was making Cassini a perfect solution for local hosting (when no 
port can be assumed as not-already-used-by-another-application).

Unfortunately it is not possible in this version (4.0) 

It seems that many parts of the application are so tight to 
Website/CassiniWebsiteConfig so that changing CreateSocketBindAndListen in 
WebsiteHost is not enough to make the mentioned feature possible.

Original issue reported on code.google.com by shayanel...@gmail.com on 20 Sep 2010 at 2:40