alexa-sdk: added locale property and optionalized

accessToken is optional, e.g. doesn't get sent on every request

types/alexa-sdk/index.d.ts

@@ -75,7 +75,7 @@ export interface SessionApplication {
 
 export interface SessionUser {
     userId: string;
-    accessToken: string;
+    accessToken?: string;
 }
 
 export interface LaunchRequest extends Request { }
@@ -105,6 +105,7 @@ export interface Request {
     type: "LaunchRequest" | "IntentRequest" | "SessionEndedRequest";
     requestId: string;
     timeStamp: string;
+    locale: string;
 }
 
 export interface ResponseBody {