Recursively check to see if child nodes are a byline before removing a node

[leibovic]

Follow-up from #40:

With the new _removeAndGetNext logic, I realize this still has the problem of not checking the children of nodes that we're about to remove (e.g. digging through a header node to look for a byline). Perhaps we should try recursively looking through nodes before removing them if we haven't found a byline yet.

[n1k0]

If we had #62 available, we could directly check for a given set of known selectors instead of recursively crawling all nodes, which is expensive; eg. document.querySelector('[rel="author"]', '[property="article:author"]') etc.