Merge branch 'php7' into feature/scheduler

Author: Marco Dania

src/Callback/Result.php

@@ -156,7 +156,7 @@ public function addExtraData($key, $value) {
     /**
      * @return string
      */
-    public function getMerchantMetaData(): string
+    public function getMerchantMetaData()
     {
         return $this->merchantMetaData;
     }
@@ -165,7 +165,7 @@ public function getMerchantMetaData(): string
      * @param string $merchantMetaData
      * @return Result
      */
-    public function setMerchantMetaData(string $merchantMetaData): Result
+    public function setMerchantMetaData($merchantMetaData)
     {
         $this->merchantMetaData = $merchantMetaData;
         return $this;
@@ -370,4 +370,4 @@ public function toArray() {
 		return $properties;
     }
 
-}
+}