[README.md] add ToC, updated installation headers, updated license description

Author: chrissimpkins

README.md

@@ -10,12 +10,20 @@
 
 <img src="https://raw.githubusercontent.com/source-foundry/uni/img/img/uni3-crunch.png" alt="uni Line Filter Example" width="99%"/>
 
-## Install
+## Contents
 
-uni is developed in Go and compiled to the command line executable `uni` (`uni.exe` on Windows).  A variety of cross-compiled binaries are available for use on Linux, macOS, and Windows systems, or you can download the source and compile the application yourself.  Instructions for both approaches follow.
+- [Installation](#installation)
+- [Usage](#usage)
+- [Issues](#issues)
+- [Contributing](#contributing)
+- [License](#license)
 
 ## Installation
 
+uni is developed in Go and compiled to the command line executable `uni` (`uni.exe` on Windows).  A variety of cross-compiled binaries are available for use on Linux, macOS, and Windows systems, or you can download the source and compile the application yourself.  Instructions for both approaches follow.
+
+## Installation Approaches
+
 ### Approach 1: Install the pre-compiled binary executable file
 
 Download the latest compiled release file for your operating system and architecture from [the Releases page](https://github.com/source-foundry/uni/releases/latest).
@@ -177,4 +185,4 @@ Contributions to the project are encouraged and welcomed. Please base your work
 
 ## License
 
-[MIT License](https://github.com/source-foundry/uni/blob/master/LICENSE)
+uni is licensed under the [MIT License](https://github.com/source-foundry/uni/blob/master/LICENSE).