Add Cisco guidelines for contributing to open-source projects

Docs/CONTRIBUTING.md

@@ -0,0 +1,45 @@
+# How to Contribute
+
+Thanks for your interest in contributing to `oauth2-swift`! Here are a few general guidelines on contributing and
+reporting bugs that we ask you to review. Following these guidelines helps to communicate that you respect the time of
+the contributors managing and developing this open source project. In return, they should reciprocate that respect in
+addressing your issue, assessing changes, and helping you finalize your pull requests. In that spirit of mutual respect,
+we endeavor to review incoming issues and pull requests within 10 days, and will close any lingering issues or pull
+requests after 60 days of inactivity.
+
+Please note that all of your interactions in the project are subject to our [Code of Conduct](CODE_OF_CONDUCT.md). This
+includes creation of issues or pull requests, commenting on issues or pull requests, and extends to all interactions in
+any real-time space e.g., Slack, Discord, etc.
+
+## Reporting Issues
+
+Before reporting a new issue, please ensure that the issue was not already reported or fixed by searching through our
+[issues list](https://github.com/slidoapp/oauth2-swift/issues).
+
+When creating a new issue, please be sure to include a **title and clear description**, as much relevant information as
+possible, and, if possible, a test case.
+
+**If you discover a security bug, please do not report it through GitHub. Instead, please see security procedures in
+[SECURITY.md](SECURITY.md) document.**
+
+## Sending Pull Requests
+
+Before sending a new pull request, take a look at existing pull requests and issues to see if the proposed change or fix
+has been discussed in the past, or if the change was already implemented but not yet released.
+
+We expect new pull requests to include tests for any affected behavior, and, as we follow semantic versioning, we may
+reserve breaking changes until the next major version release.
+
+## Other Ways to Contribute
+
+We welcome anyone that wants to contribute to `oauth2-swift` to triage and reply to open issues to help troubleshoot
+and fix existing bugs. Here is what you can do:
+
+- Help ensure that existing issues follows the recommendations from the _[Reporting Issues](#reporting-issues)_ section,
+  providing feedback to the issue's author on what might be missing.
+- Review existing pull requests, and testing patches against real existing applications that use `oauth2-swift` library.
+- Write a test, or add a missing test case to an existing test.
+
+Thanks again for your interest on contributing to `oauth2-swift` project!
+
+:heart:

README.md

@@ -12,7 +12,7 @@ OAuth2 frameworks for **macOS**, **iOS** and **tvOS** written in Swift 5.
 - [📖 Technical Documentation](https://p2.github.io/OAuth2)
 
 OAuth2 requires Xcode 12.4, the built framework can be used on **OS X 10.15** or **iOS 12** and later.
-Happy to accept pull requests, please see [CONTRIBUTING.md](./CONTRIBUTING.md)
+Happy to accept pull requests, please see [CONTRIBUTING.md](./Docs/CONTRIBUTING.md)
 
 ### Swift Version