* Returns parsed data from a given file and language key.
*
* @param string $fileReference Input is a file-reference (see \TYPO3\CMS\Core\Utility\GeneralUtility::getFileAbsFileName). That file is expected to be a supported locallang file format
* @param string $languageKey Language key
* @param string $charset Character set (option); if not set, determined by the language key
* @param integer $errorMode Error mode (when file could not be found): 0 - syslog entry, 1 - do nothing, 2 - throw an exception$
* @param boolean $isLocalizationOverride TRUE if $fileReference is a localization override