Proposal for Support CORS (Cross-Origin Resource Sharing) #216

Add a Filter to handle multiple resources and a Helper to add CORS headers manually.
Could you explain the use case for allowOnlyRequestedMethod = true?  If I understand it correctly, it would echo back the requested method as an allowed method, without regard to whether that method was actually supported by the resource.  In fact, it could end up conflicting with the returned "Allow" response header.