Update Contrib to always use https, and repack MathJax.js

Author: dpvc

MathJax.js

@@ -666,8 +666,7 @@ MathJax.cdnFileVersions = {};  // can be used to specify revisions for individua
 
   var PATH = {};
   PATH[BASENAME] = "";  // empty path gets the root URL
-  PATH.Contrib = (String(location.protocol).match(/^https?:/) ? "" : "http:") +
-                   "//cdn.mathjax.org/mathjax/contrib";   // the third-party extensions
+  PATH.Contrib = "https://cdn.mathjax.org/mathjax/contrib";   // the third-party extensions
 
   BASE.Ajax = {
     loaded: {},         // files already loaded