function matchesTag(node, exp) {
	return (
		node.nodeType === 1 &&
		(exp.tag === '*' || node.nodeName.toLowerCase() === exp.tag)
	);
}
function matchesTag(node, exp) {
	return (
		node.nodeType === 1 &&
		(exp.tag === '*' || node.nodeName.toLowerCase() === exp.tag)
	);
}
function matchesTag ( node , exp ) { return ( node . nodeType === 1 && ( exp . tag === '*' || node . nodeName . toLowerCase ( ) === exp . tag ) ) ; }
todo: implement an option to follow aria-owns
todo : implement an option to follow aria - owns
Returns true if node matches the tag