Fixes codegangsta#1 and codegangsta#3

Issue 1: Create README
Issue 3: Add instructions on installing Go

README.md

@@ -0,0 +1,30 @@
+# essential-go
+
+![Repo Size](https://img.shields.io/github/repo-size/codegangsta/essential-go?style=for-the-badge)
+![Go](https://img.shields.io/badge/Go-00ADD8?style=for-the-badge&logo=go&logoColor=white)
+
+## 📦 Installation
+
+- [Download](https://go.dev/dl/) the binary release suitable for your system
+- Start [installation](https://go.dev/doc/install) process by selecting the
+  tab for your computer's operating system
+
+For more indepth installation process:
+- For [Windows](https://www.youtube.com/watch?v=kxD8p-aPYzM)
+- For [Linux](https://www.youtube.com/watch?v=nQPdj4Z25Js)
+- For [Mac](https://www.youtube.com/watch?v=dgIh-VYcWYw&pp=ygUZaG93IHRvIGluc3RhbGwgZ29sYW5nIG1hYw%3D%3D)
+
+## 📄 Table of content
+
+- [First go program](./your-first-go-program/main.go)
+- [Functions](./functions/main.go)
+- [Variables](./variables/main.go)
+- [Types](./types/main.go)
+- [Arrays and Slices](./arrays-and-slices/main.go)
+- [Maps](./maps/main.go)
+- [Pointers](./pointers/main.go)
+- [Control structures](./control-structures/main.go)
+- [Pub](./pub/main.go)
+- [Interfaces](./interfaces/main.go)
+- [JSON parser](./json-parser/main.go)
+- [HTTP file server](./http-file-server/main.go)