Create CONTRIBUTING.md

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644 (file)
index 0000000..c54570a
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,3 @@
+# How to contribute
+
+Fairly simple - raise a PR. All PRs should fix a single issue and have an existing issue they resolve.