Merge pull request #1522 from dpvc/issue1519

Add Contrib to the Ajax paths. #1519

unpacked/MathJax.js

@@ -659,6 +659,8 @@ MathJax.cdnFileVersions = {};  // can be used to specify revisions for individua
   
   var PATH = {};
   PATH[BASENAME] = "";  // empty path gets the root URL
+  PATH.Contrib = (String(location.protocal).match(/^https?:/) ? "" : "http:") +
+                   "//cdn.mathjax.org/mathjax/contrib";   // the third-party extensions
   
   BASE.Ajax = {
     loaded: {},         // files already loaded