function spacePad( str, width, right ) {
	var pad = width - str.length;
	if ( pad < 0 ) {
		return str;
	}
	str = ( right ) ?
		str + spaces( pad ) :
		spaces( pad ) + str;
	return str;
}
Pads a token with spaces to the specified width.

@private
@param {string} str - token argument
@param {number} width - token width
@param {boolean} [right=false] - boolean indicating whether to pad to the right
@returns {string} padded token argument