Do the right thing when we have a username but no password

With a username parameter but no password parameter we'll attribute edits to that username, but not require authentication.

core/modules/server/routes/get-status.js

@@ -19,7 +19,7 @@ exports.path = /^\/status$/;
 exports.handler = function(request,response,state) {
 	response.writeHead(200, {"Content-Type": "application/json"});
 	var text = JSON.stringify({
-		username: state.authenticatedUsername,
+		username: state.authenticatedUsername || state.server.get("username") || "",
 		space: {
 			recipe: "default"
 		},