code: function createElement(el, attrs) {
          var newEl = document.createElement(el);
  
          attrs = attrs || {};
          if (attrs.className) {
              Dom.addClass(newEl, attrs.className);
          }
  
          if (attrs.styles) {
              setStyles(newEl, attrs.styles);
          }
  
          if (attrs.parent) {
              attrs.parent.appendChild(newEl);
          }
  
          if (attrs.id) {
              newEl.setAttribute("id", attrs.id);
          }
  
          if (attrs.content) {
              if (attrs.content.nodeName) {
                  newEl.appendChild(attrs.content);
              } else {
                  newEl.innerHTML = attrs.content;
              }
          }
  
          return newEl;
      }
docs: Create an element, set its class name and optionally install the element
  to its parent.
  @method createElement
  @param el {String} The element to be created
  @param attrs {Object} Configuration of parent, class and id attributes.
  If the content is specified, it is inserted after creation of the
  element. The content can also be an HTML element in which case it would
  be appended as a child node of the created element.
  @private