Move private APIs to private namespace

Fixes #2078

src/html/requireHtml.js

@@ -2,7 +2,7 @@
 var jasmineRequire = window.jasmineRequire || require('./jasmine.js');
 
 jasmineRequire.html = function(j$) {
-  j$.ResultsNode = jasmineRequire.ResultsNode();
+  j$.private.ResultsNode = jasmineRequire.ResultsNode();
   j$.HtmlReporter = jasmineRequire.HtmlReporter(j$);
   j$.QueryString = jasmineRequire.QueryString();
   j$.HtmlSpecFilter = jasmineRequire.HtmlSpecFilter();