renamed 'Invalid data...' to 'Invalid parent'

Author: mxschmitt

src/API.php

@@ -94,7 +94,7 @@ public function getFiles()
  }
  }
  if (count($todo) !== 0) {
- throw new \Exception('Inconsistent data...');
+ throw new \Exception('Invalid parent');
  }
  return $out;
  }