[access-control] If-Method-Allowed -> Method-Check

Hi,

I renamed If-Method-Allowed to Method-Check as Ian Hickson pointed out  
that the header doesn't share the semantics of other If-* headers. As far  
as I can tell this shouldn't affect anyone as there are no implementations  
of If-Method-Allowed yet.

Kind regards,


-- 
Anne van Kesteren
<http://annevankesteren.nl/>
<http://www.opera.com/>