Prevent caching of responses by NSURLCache (fix #211)

@@ -248,4 +248,11 @@
     [self done];
     [self done];
 }
 }
 
 
+- (NSCachedURLResponse *)connection:(NSURLConnection *)connection willCacheResponse:(NSCachedURLResponse *)cachedResponse
+{
+    // Prevents caching of responses
+    return nil;
+}
+
+
 @end
 @end