merging pull request #83 from AMilkov

Check if there is avatar before going into upload scenario.

Otherwise the button "Upload avatar" from edit profile form generate msg:
"Avatar image can not be blank"

Author: thyseus

avatar/controllers/YumAvatarController.php

@@ -58,7 +58,7 @@ public function actionEditAvatar($id = null) {
 		if(!$model)
 			throw new CHttpException(404);
 
-		if(isset($_POST['YumUser'])) {
+		if(isset($_POST['YumUser']) && isset($_POST['YumUser']['avatar'])) {
 			$model->attributes = $_POST['YumUser'];
 			$model->setScenario('avatarUpload');