Merge pull request #1 from github/zkoppert-patch-1

Add installation, Commands, and Contribution sections to README

README.md

@@ -1,2 +1,28 @@
 # gh-classroom
 GitHub Classroom CLI Extension is a powerful and easy-to-use command line tool that enhances the functionality of the GitHub CLI, specifically tailored for educators using GitHub Classroom. 
+
+## Installation
+
+Install the CLI
+
+```bash
+brew install gh
+```
+
+Install this extension
+
+```bash
+gh extension install github/gh-classroom
+```
+
+## Commands
+
+For more information and a list of available commands
+
+```bash
+gh classroom -h
+```
+
+## Contributions
+
+At this time we are not open to contributions but hang tight as we are working towards that goal!