This PR avoids some issues in can-vdom in setting up the SSR text
explicitly imports can-vdom to set up the appropriate globals
sets LoaderPolyfill on the global, since it is used deeply in the lib code
uses lastChild instead of firstChild when parsing the HTML returned from autorender, because the first child is a text node of the !DOCTYPE tag (will create a separate issue for this)
This PR avoids some issues in can-vdom in setting up the SSR text