Change mathjax script type

Chrome won't execute this if it's not marked as js

Author: mattico

src/theme/index.hbs

@@ -240,7 +240,7 @@
 
         {{#if is_print}}
         {{#if mathjax_support}}
-        <script type="text/x-mathjax-config">
+        <script type="text/javascript">
         MathJax.Hub.Register.StartupHook("End", function() {
             window.print();
         });