add MathJax options

lib/views/layout/layout.html

@@ -47,7 +47,11 @@
         jax: ["input/TeX", "output/SVG"],
         tex2jax: {
           processEscapes: true
-        }
+        },
+        showMathMenu: false,
+        showMathMenuMSIE: false,
+        showProcessingMessages: false,
+        messageStyle: "none"
       });
     </script>
     <script src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/MathJax.js" async></script>