Updated/extended README.

README.md

@@ -1,5 +1,19 @@
 # TINS 2020
 
+## Content
+
+- [Introduction](##Introduction)
+- [Additional Rules](##Additional-Rules)
+   * [Implementation](###Implementation)
+   * [Definition](###Definition)
+- [Building](##Building)
+- [Sources](##Sources)
+- [Licenses (third party)](##Licenses)
+   * [Go-SDL2](###Go-SDL2)
+   * [SDL 2.0](###SDL-2.0)
+   * [Fira Mono font](###Fira-Mono-font)
+   * [Open Sans font](###Open-Sans-font)
+
 ## Introduction
 
 **Welcome to Botanim!**
@@ -19,7 +33,9 @@ Flowers can only grow (well) in certain climates based on two properties: humidi
 
 Have fun playing!
 
-## Rules
+## Additional Rules
+
+### Implementation
 
 **genre rule #130**
 This rule is the most obvious. The goal of the game is to grow flowers so given enough time and a bit of luck your screen will be full of flowers.
@@ -33,9 +49,7 @@ The terrain is based on (several: humidity, temperature, placement of props, var
 **technical rule #68**
 The description of the flowers will scroll below the icon of the "buy flower" buttons when hovered.
 
-## Implementation
+### Definition
-
-## Additional Rules
 
 ### Genre requirement
 **** There will be 1 genre rule
@@ -82,8 +96,8 @@ Comments: Lots of wiggle room here. For example, you could revert the last techn
 Prerequisites:
 - [SDL 2.0](https://www.libsdl.org/) (SDL2, SDL2_image, SDL2_ttf and SDL2_gfx development libraries are required; for [more information](https://github.com/veandco/go-sdl2)).
 - [Go](https://golang.org/dl/) 1.12 or later.
-- GCC.
+- GCC or a compatible compiler.
-- Git.
+- [Git](https://git-scm.com/download).
 
 With all prequisites installed you can run:
 ```