chore(#148): add Contributing guide

CONTRIBUTING.md

@@ -0,0 +1,24 @@
+---
+title: Contributing
+weight: 5
+---
+
+> All contributions are welcomed and appreciated.
+
+Druxt is an open source project, built, supported and maintained by the community, for the community.
+
+* * *
+
+## Bug reports and feature requests
+
+One of the easiest ways to contribute to Druxt is to open issues, giving as much detail as possible to make it easier other contributors and maintainers: http://github.com/druxt/druxt.js/issues/new/choose
+
+When reporting bugs please make sure to provide detailed steps to reproduce the issue, and when possible provide a GitPod workspace snapshot to demonstrate the issue.
+
+* * *
+
+## Pull Requests
+
+@TODO
+
+* * *