Add HTML header for MathJax

Author: Sampreet

_includes/head.html

@@ -0,0 +1,25 @@
+<script type="text/x-mathjax-config">
+    MathJax.Hub.Config({
+        extensions: ["tex2jax.js"],
+        jax: ["input/TeX", "output/HTML-CSS"],
+        tex2jax: {
+            skipTags: ['script', 'noscript', 'style', 'textarea', 'pre'],
+            inlineMath: [
+                ['$', '$'],
+            ],
+            displayMath: [
+                ['$$', '$$'],
+            ],
+            processEscapes: true,
+        },
+        TeX: {
+            equationNumbers: {
+                autoNumber: "all",
+            },
+        },
+        "HTML-CSS": {
+            availableFonts: ["TeX"],
+        },
+    });
+</script>
+<script src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML" type="text/javascript"></script>