Revert "Remove katex support, for now"

This reverts commit 56f7738d6e.

exampleSite/config.toml

@@ -23,6 +23,7 @@ enableGitInfo = true
   # For more date formats see https://gohugo.io/functions/format/
   dateFormat = "Jan 2, 2006"
   codePenUser = "someUser"
+  katex = true
 
 [menu]
   [[menu.nav]]

exampleSite/config.yaml

@@ -23,6 +23,7 @@ params:
   # For more date formats see https://gohugo.io/functions/format/
   dateFormat: Jan 2, 2006
   codePenUser: someUser
+  katex: true
 
 menu:
   nav:

exampleSite/content/post/katex-math-typesetting/index.md

@@ -0,0 +1,29 @@
+---
+title: "Katex Math Typesetting"
+date: 2019-03-28
+tags: [katex, math, typesetting, hugo]
+---
+
+Enable Katex in the config file by setting the `katex` param to `true`. This will import the necessary Katex CSS/JS. 
+
+**Note:** Use the online reference of [supported TeX functions](https://katex.org/docs/supported.html). 
+
+Some math:
+
+```
+$$ \varphi = \dfrac{1+\sqrt5}{2}= 1.6180339887… $$
+```
+
+$$ \varphi = \dfrac{1+\sqrt5}{2}= 1.6180339887… $$
+
+More math: 
+
+```
+$$
+\varphi = 1+\frac{1} {1+\frac{1} {1+\frac{1} {1+\cdots} } } 
+$$
+```
+
+$$
+\varphi = 1+\frac{1} {1+\frac{1} {1+\frac{1} {1+\cdots} } } 
+$$