#getQuerySelector
returns the query selector for a given dom node. The result can be directly fed to document.querySelector. It uses body, #ids and :nth-child(i) to compose the selector.
##Usage
var getQuerySelector = require("get-query-selector");
var aNodes = document.getElementByTagName("A");
var aNode = aNodes[aNodes.length - 1];
var selector = getQuerySelector(aNode);