fix #157 show screen_name when name is empty in retweet

src/components/status/status.js

@@ -87,7 +87,7 @@ const Status = {
       }
     },
     retweet () { return !!this.statusoid.retweeted_status },
-    retweeter () { return this.statusoid.user.name },
+    retweeter () { return this.statusoid.user.name || this.statusoid.user.screen_name },
     retweeterHtml () { return this.statusoid.user.name_html },
     status () {
       if (this.retweet) {