Merge pull request 'add interface IAuthenticationRequired' (#4) from feature/interface-for-authentication-required into master

Reviewed-on: #4

src/Interfaces/Authentication/IAuthenticationRequired.php

@@ -0,0 +1,6 @@
+<?php namespace SokoWeb\Interfaces\Authentication;
+
+interface IAuthenticationRequired
+{
+    public function isAuthenticationRequired(): bool;
+}

src/PersistentData/PersistentDataManager.php

@@ -57,7 +57,7 @@ class PersistentDataManager
             $value = current($data);
             $relation = key($relations);
 
-            if (strpos($key, '__') == false) {
+            if (strpos($key, '__') === false) {
                 $method = 'set' . str_replace('_', '', ucwords($key, '_'));
 
                 if (method_exists($model, $method) && isset($value)) {