Add possible parameter values for the field function documentation and error message

[Liblastic]

docblock example @param string $new_lines New line handling way. Possible values: 'wpautop', 'br', ''.

Error message suggestion: For example ( new Textarea( 'test' ) )->set_new_lines( 'wrong-parameter-value' ) could return error message:

throw new \Geniem\ACF\Exception( 'Geniem\ACF\Textarea: set_new_lines() does not accept argument "' . $new_lines . ' Possible values' . implode( $possible_values, ', ' ) . '"' );