Reviewed WSF_REQUEST.item (..) and items to look into Form, Query, and Path (cookie are excluded for security)

Added WSF_REQUEST.path_parameter (a_name): detachable WSF_VALUE
   - fill path_parameters using `import_raw_path_parameters"
     when executing the route
   - reset to previous value with reset_path_parameters (..),
     just in case the request is executed via severals routes.

library/server/wsf/router/uri/wsf_uri_handler_context.e

@@ -26,6 +26,18 @@ feature {NONE} -- Initialization
 			path := p
 		end
 
+feature -- Request data
+
+	apply (req: WSF_REQUEST)
+			-- <Precursor>
+		do
+		end
+
+	revert (req: WSF_REQUEST)
+			-- <Precursor>
+		do
+		end
+
 feature -- Item		
 
 	item (a_name: READABLE_STRING_32): detachable WSF_VALUE