function type(node){
  utils.assertPresent(node, 'expression');
  return node.nodeName;
}
Return type of `node`.

Examples:

   type(12)
   // => 'unit'

   type(#fff)
   // => 'color'

   type(type)
   // => 'function'

   type(unbound)
   typeof(unbound)
   type-of(unbound)
   // => 'ident'

@param {Node} node
@return {String}
@api public