Add see also section to posts footer (#152)

Joseph Ting

11.21.2019 27e83b1e5a9d8b7bbd42d202bd5ef57adcce659b

 exampleSite/content/posts/external-post.md

@@ -11,4 +11,5 @@
    "Development",
]
externalLink = "https://github.com/luizdepra/hugo-coder/wiki"
series = ["Hugo"]
+++