FIXED : CI : Error with the generation of the PHPDoc

Deprecated: phpDocumentor2 should be run from the phpdoc file, not phpdoc.php in /home/travis/build/PHPOffice/PHPWord/vendor/phpdocumentor/phpdocumentor/bin/phpdoc.php on line 13

Refs : https://github.com/phpDocumentor/phpDocumentor2/blob/395af1d42a3fe8af7eedeea28e530ab2fdd2bd06/bin/phpdoc.php