Create CONTRIBUTING.md

CONTRIBUTING.md

+## Submitting issues
+
+If you have questions about how to use ownCloud, please direct these to the [Mailinglist][mailinglist] discussion list or our [Forum][forum]. We are also available on [IRC][irc].
+
+### Guidelines
+* Search the existing issues first, it's likely that your issue was already reported.
+* Ensure that you're in the right repository, apps are likely to be developed in the apps repo and our client in the mirall repo.
+* An example demonstrating your problem, is likely to get an answer faster.
+
+If your issue appears to be a bug, and hasn't been reported, open a new issue. Please ensure that you're in the right repository. This is *only* for bugs in the core code. For other bugs: Please check if there is a [better suited repository](https://github.com/owncloud).
+
+Help us to maximize the effort we can spend fixing issues and adding new features, by not reporting duplicate issues.
+
+[mailinglist]: https://mail.kde.org/mailman/listinfo/owncloud
+[forum]: http://forum.owncloud.org/
+[irc]: http://webchat.freenode.net/?channels=owncloud&uio=d4
+
+## Contributing to Source Code
+
+Thanks for wanting to contribute source code to ownCloud. That's great!
+
+Before we're able to merge your code into the ownCloud core, you need to sign our [Contributor Agreement][agreement].
+
+Please read the [Developer Manuals][devmanual] to get useful info like how to create your first application or test the ownCloud code.
+
+**TRANSLATIONS**
+Please submit translations via [Transifex][transifex].
+
+[transifex]: https://www.transifex.com/projects/p/owncloud/
+[agreement]: http://owncloud.org/about/contributor-agreement/
+[list]: https://groups.google.com/forum/?fromgroups#!forum/angular
+[devmanual]: http://owncloud.org/dev/