Added AuthenticationScheme to CopyWithZone

The CopyWithZone method did not copy the authenticationScheme, resulting
in problems when using a copied ASIHTTPRequest.

@@ -10,3 +10,4 @@ profile
 *.pbxuser
 *.mode1v3
 External/GHUnit/*
+.svn
\ No newline at end of file

@@ -4081,6 +4081,7 @@ static NSOperationQueue *sharedQueue = nil;
 	[newRequest setShouldUseRFC2616RedirectBehaviour:[self shouldUseRFC2616RedirectBehaviour]];
 	[newRequest setShouldAttemptPersistentConnection:[self shouldAttemptPersistentConnection]];
 	[newRequest setPersistentConnectionTimeoutSeconds:[self persistentConnectionTimeoutSeconds]];
+    [newRequest setAuthenticationScheme:[self authenticationScheme]];
 	return newRequest;
 }