adding CONTRIBUTING.md and linking to CLA's in gitlab-ce

CONTRIBUTING.md

@@ -0,0 +1,16 @@
+## Contributing to GitLab Multi Runner
+
+Contributions are welcome!
+
+The official repository for this project is on [GitLab.com](https://gitlab.com/gitlab-org/gitlab-ci-multi-runner).
+
+* [Development](docs/development/README.md)
+* [Issues](https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/issues)
+* [Merge Requests](https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/merge_requests)
+
+## Contributor license agreement
+
+By submitting code as an individual you agree to the
+[individual contributor license agreement](https://gitlab.com/gitlab-org/gitlab-ce/doc/legal/individual_contributor_license_agreement.md).
+By submitting code as an entity you agree to the
+[corporate contributor license agreement](https://gitlab.com/gitlab-org/gitlab-ce/doc/legal/corporate_contributor_license_agreement.md).

README.md

@@ -10,13 +10,8 @@ The old name of this project was GitLab CI Multi Runner but please use "GitLab R
 
 ### Contributing
 
-The official repository for this project is on [GitLab.com](https://gitlab.com/gitlab-org/gitlab-ci-multi-runner).
+Contributions are welcome, see [`CONTRIBUTING.md`](CONTRIBUTING.md) for more details.
 
-* [Development](docs/development/README.md)
-* [Issues](https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/issues)
-* [Merge Requests](https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/merge_requests)
-
-Contributions are welcome, per the [contribution guidelines](https://gitlab.com/gitlab-org/gitlab-ce/CONTRIBUTING.md) and the contributor license agreements linked to from there.
 
 #### Closing issues and merge requests