minor #9 Fix fatal error (Lctrs)

This PR was merged into the 0.4.x-dev branch.

Discussion
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Fix fatal error

Fatal error: Cannot use Xabbuh\XApi\Model\Actor as Actor because the name is already in use in /srv/app/vendor/php-xapi/repository-doctrine/src/Mapping/Object.php on line 16

Commits
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9c30206 Fix fatal error

Author: xabbuh

src/Mapping/Object.php

@@ -13,7 +13,7 @@
 
 use Xabbuh\XApi\Model\Account;
 use Xabbuh\XApi\Model\Activity;
-use Xabbuh\XApi\Model\Actor;
+use Xabbuh\XApi\Model\Actor as ActorModel;
 use Xabbuh\XApi\Model\Agent;
 use Xabbuh\XApi\Model\Definition;
 use Xabbuh\XApi\Model\Group;
@@ -181,7 +181,7 @@ class Object
 
     public static function fromModel(ObjectModel $model)
     {
-        if ($model instanceof Actor) {
+        if ($model instanceof ActorModel) {
             return self::fromActor($model);
         }
 
@@ -265,7 +265,7 @@ private static function fromActivity(Activity $model)
         return $object;
     }
 
-    private static function fromActor(Actor $model)
+    private static function fromActor(ActorModel $model)
     {
         $inverseFunctionalIdentifier = $model->getInverseFunctionalIdentifier();