Custom stream wrapper support

Added support for custom stream wrappers, such as "fly" or "s3".
Support is determined per reader.

src/Spout/Reader/XLSX/Reader.php

@@ -37,6 +37,16 @@ class Reader extends AbstractReader
         return $this;
     }
 
+    /**
+     * Returns whether stream wrappers are supported
+     *
+     * @return bool
+     */
+    protected function doesSupportStreamWrapper()
+    {
+        return false;
+    }
+
     /**
      * Opens the file at the given file path to make it ready to be read.
      * It also parses the sharedStrings.xml file to get all the shared strings available in memory