Split the string into an array of words.
Twine\Str::words( void ) : array
$string = new Twine\Str('john pinkerton');
$string->words(); // Returns ['john', 'pinkerton']
$string = new Twine\Str('johnPinkerton');
$string->words(); // Returns ['john', 'Pinkerton']
$string = new Twine\Str('john_pinkerton');
$string->words(); // Returns ['john', 'pinkerton']
$string = new Twine\Str('john-pinkerton');
$string->words(); // Returns ['john', 'pinkerton']
$string = new Twine\Str('JohnPinkerton');
$string->words(); // Returns ['John', 'Pinkerton']