headers.rb in http-protocol-0.17.0

- old
+ new

@@ -28,9 +28,10 @@
 		CONNECTION = 'connection'.freeze
 		CLOSE = 'close'.freeze
 		KEEP_ALIVE = 'keep-alive'.freeze
 		
 		HOST = 'host'.freeze
+		UPGRADE = 'upgrade'.freeze
 		
 		class Headers
 			class Split < Array
 				COMMA = /\s*,\s*/
 				