refactor(User): set user name and user token as member variable

src/user.ts

@@ -1,28 +1,36 @@
 import * as vscode from 'vscode';
+import * as path from 'path';
+import * as os from 'os';
 
 export default class User {
     private context:vscode.ExtensionContext;
+    private username:string|undefined;
+    private userToken:string|undefined;
     private usernameKey:string = 'devstarUsername'
     private userTokenKey:string = 'devstarUserToken'
 
     constructor(context: vscode.ExtensionContext) {
         this.context = context;
+        this.username = this.context.globalState.get(this.usernameKey);
+        this.userToken = this.context.globalState.get(this.userTokenKey);
     }
 
     public getUsernameFromLocal(): string|undefined {
-        return this.context.globalState.get(this.usernameKey);
+        return this.username;
     }
 
     public getUserTokenFromLocal(): string|undefined{
-        return this.context.globalState.get(this.userTokenKey);
+        return this.userToken;
     }
 
     public setUsernameToLocal(username:string) {
-        this.context.globalState.update(this.usernameKey, username)
+        this.context.globalState.update(this.usernameKey, username);
+        this.username = username;
     }
 
     public setUserTokenToLocal(userToken:string) {
         this.context.globalState.update(this.userTokenKey, userToken)
+        this.userToken = userToken
     }
 
 }