one last exciting unicode fix

screenless/bureau/mailroom/mailroom.py

@@ -140,7 +140,7 @@ class MailRoom(Bureau):
         with self.dbenv.begin(db=self.postdb_rev, write=True) as txn:
             shortcode = txn.get(msgid)
             if shortcode is not None:
-                return shortcode
+                return shortcode.decode("utf-8")
             else:
                 shortcode = ''.join(random.choice(string.ascii_letters + 
                                     string.digits) for _ in range(5)).encode()
@@ -148,7 +148,7 @@ class MailRoom(Bureau):
                 txn.put(msgid, shortcode)
         with self.dbenv.begin(db=self.postdb, write=True) as txn:
             txn.put(shortcode, msgid)
-        return shortcode.decode()
+        return shortcode.decode("utf-8")
 
     @add_command("fax", "Send a Document Camera Image via Email")
     def fax(self, data):