Update Redactor.php

My server couldn't find the language files. I managed to fix it by changing this line in Redactor.php:

65: $options = CJSON::encode(array_merge($this->editorOptions, array('lang' => $this->lang, 'toolbar' => $this->toolbar)));

for this one:

65: $options = CJSON::encode(array_merge($this->editorOptions, array('path' => $assets ,'lang' => $this->lang, 'toolbar' => $this->toolbar)));