Merge pull request #1 from github/hohn-readme

Basic README

README.md

@@ -1,2 +1,18 @@
-# codeql-training-material
-Material for teaching CodeQL.
+# Introduction
+This repository contains material for teaching CodeQL.  The presentations are
+split by the programming language they present, currently c++,  csharp,  go,  java
+and javascript.
+
+# Contributing
+Depending on the contribution, use a single file or a directory.
+- Single-file presentations are in their language's directory, e.g., 
+  `java/workshop-java-mismatched-loop-condition.md`
+- Multi-file presentations use whole directories, e.g., `c++/introduction/` houses
+  `codeql-workshop-for-cpp.md` and several subdirectories.
+
+While this repository is private, new content can be pushed directly to master.
+Minor fixes (typos, broken urls, grammar, etc.) likewise don't benefit from a pull
+request and can be pushed directly.  Significant changes should use a pull
+request.
+
+