Updated the default rescue response (i.e when exception or bad internal error occurs).

Factorized the implementation in WGI_RESCUE_EXECUTION, and now by redefining the `WGI_EXECUTION.execute_rescue (...)` procedure, it is possible to have a custom response on such rescued execution.

library/server/ewsgi/connectors/cgi/src/wgi_cgi_connector.e

@@ -38,12 +38,12 @@ feature -- Execution
 				exec.execute
 				res.push
 				exec.clean
+			elseif exec /= Void then
+				exec.execute_rescue ((create {EXCEPTION_MANAGER}).last_exception)
+				exec.clean
 			else
-				process_rescue (res)
-				if exec /= Void then
-					exec.clean
-				end
-			end
+				(create {WGI_RESCUE_EXECUTION}).execute (req, res, (create {EXCEPTION_MANAGER}).last_exception)
+			end				
 		rescue
 			if not rescued then
 				rescued := True
@@ -51,24 +51,6 @@ feature -- Execution
 			end
 		end
 
-	process_rescue (res: detachable WGI_RESPONSE)
-			-- Handle rescued execution of current request.
-		do
-			if attached (create {EXCEPTION_MANAGER}).last_exception as e and then attached e.trace as l_trace then
-				if res /= Void then
-					if not res.status_is_set then
-						res.set_status_code ({HTTP_STATUS_CODE}.internal_server_error, Void)
-					end
-					if res.message_writable then
-						res.put_string ("<pre>")
-						res.put_string (html_encoder.encoded_string (l_trace))
-						res.put_string ("</pre>")
-					end
-					res.push
-				end
-			end
-		end
-
 note
 	copyright: "2011-2015, Eiffel Software and others"
 	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"