Merge pull request #1270 from peterschrammel/contribute-readme

Contributing section in readme

Author: Daniel Kroening

README.md

@@ -15,6 +15,31 @@ and passing the resulting equation to a decision procedure.
 
 For full information see [cprover.org](http://www.cprover.org/cbmc).
 
+Versions
+========
+
+Get the [latest release](https://github.com/diffblue/cbmc/releases)
+* Releases are tested and for production use.
+
+Get the current *develop* version: `git clone https://github.com/diffblue/cbmc.git`
+* Develop versions are not recommended for production use.
+
+Report bugs
+===========
+
+If you encounter a problem please file a bug report:
+* Create an [issue](https://github.com/diffblue/cbmc/issues)
+
+Contributing to the code base
+=============================
+
+1. Fork the repository
+2. Clone the repository `git clone [email protected]:YOURNAME/cbmc.git`
+3. Create a branch from the `develop` branch (default branch)
+4. Make your changes (follow the [coding guidelines](https://github.com/diffblue/cbmc/blob/develop/CODING_STANDARD.md))
+5. Push your changes to your branch
+6. Create a Pull Request targeting the `develop` branch
+
 License
 =======
 4-clause BSD license, see `LICENSE` file.