code: function getHTML(sel) {
  	sel = sel || getSelection();
  	if (!sel.rangeCount || sel.isCollapsed) { return null; }
  
  	var len = sel.rangeCount;
  	var container = doc.createElement('div');
  
  	for (var i = 0; i < len; ++i) {
  		container.appendChild(sel.getRangeAt(i).cloneContents());
  	}
  
  	return container.innerHTML;
  }
docs: Get the inner HTML content of a selection.
  @see http://stackoverflow.com/questions/4652734/return-html-from-a-user-selected-text/4652824#4652824
  @param {Selection} sel
  @return {String}