Use a shortened CONTRIBUTING blurb in README, and point to handbook

CONTRIBUTING.md

@@ -7,37 +7,4 @@ We appreciate you taking the initiative to contribute to WP-CLI. It’s because
 
 **Contributing isn’t limited to just code.** We encourage you to contribute in the way that best fits your abilities, by writing tutorials, giving a demo at your local meetup, helping other users with their support questions, or revising our documentation.
 
-Please take a moment to read these guidelines at depth. Following the guidelines helps to communicate that you respect the time of the other contributors to the project. In turn, they’ll do their best to reciprocate that respect when working with you, across timezones and around the world.
+Read through our [contributing guidelines in the handbook](https://make.wordpress.org/cli/handbook/contributing/) for a thorough introduction to how you can get involved. Following these guidelines helps to communicate that you respect the time of other contributors on the project. In turn, they’ll do their best to reciprocate that respect when working with you, across timezones and around the world.
-
-### Reporting a bug
-
-Think you’ve found a bug? We’d love for you to help us get it fixed.
-
-Before you create a new issue, you should [search existing issues](https://github.com/wp-cli/wp-cli/issues?utf8=%E2%9C%93&q=label%3Abug%20) to see if there’s an existing resolution to it, or if it’s already been fixed in a newer version of WP-CLI. You should also check our [documentation on common issues and their fixes](https://wp-cli.org/docs/common-issues/).
-
-Once you’ve done a bit of searching and discovered there isn’t an open or fixed issue for your bug, please [follow our guidelines for submitting a bug report](http://wp-cli.org/docs/bug-reports/) to make sure it gets addressed in a timely manner.
-
-### Creating a pull request
-
-Want to contribute a new feature? WP-CLI is a mature project, and already chock-full of useful functionality. Please first [open a new issue](https://github.com/wp-cli/wp-cli/issues/new) to discuss whether the feature is a good fit for WP-CLI core, or might be better suited as a [community package](https://wp-cli.org/package-index/).
-
-New to the WP-CLI codebase? Check out [issues labeled 'good-first-issue'](https://github.com/wp-cli/wp-cli/labels/good-first-issue) for a place to start. These issues are specially earmarked for new contributors.
-
-Once you've decided to commit the time to seeing your pull request through, please [follow our guidelines for creating a pull request](https://wp-cli.org/docs/pull-requests/) to make sure it's a pleasant experience.
-
-### Improving our documentation
-
-Is documentation your strength? Take a look at the currently open [documentation issues](https://github.com/wp-cli/wp-cli/issues?q=is%3Aopen+is%3Aissue+label%3Ascope%3Adocumentation) and see if you can tackle any of those.
-
-If you believe you’ve found an issue with the documentation, you should [search existing issues](https://github.com/wp-cli/wp-cli/issues?utf8=%E2%9C%93&q=label%3Abug%20) to see if there’s an existing resolution to it, or if it’s already been fixed in a newer version of WP-CLI.
-
-There are a couple different types of documentation currently part of WP-CLI:
-
-* Documentation for individual WP-CLI commands (anything underneath [http://wp-cli.org/commands](http://wp-cli.org/commands)) is contained in the PHPDoc for each command. This means that to edit the documentation for a command, you will need to edit the file that actually provides the functionality for that command. The web documentation is generated from these files at the time of release, so you may not see your changes until the next release.
-* Individual documentation pages (anything under [http://wp-cli.org/docs/](http://wp-cli.org/docs/) can be edited by contributing to the [wp-cli.github.com repository on GitHub](https://github.com/wp-cli/wp-cli.github.com). You don't necessarily need to navigate the Github repo though; any page that is part of this repository will have an 'Edit' link in the top right of the page which will take you to the corresponding file on GitHub.
-
-### Contributing in other ways
-
-Feel free to [create an issue](https://github.com/wp-cli/wp-cli/issues/new) with your question, and we'll see if we can find an answer for it.
-
-Alternatively, if you have a WordPress.org account, you may also consider joining the `#cli` channel on the [WordPress.org Slack organization](https://make.wordpress.org/chat/).

README.md

@@ -175,7 +175,7 @@ We appreciate you taking the initiative to contribute to WP-CLI. It’s because
 
 **Contributing isn’t limited to just code.** We encourage you to contribute in the way that best fits your abilities, by writing tutorials, giving a demo at your local meetup, helping other users with their support questions, or revising our documentation.
 
-Please take a moment to [read these guidelines at depth](https://wp-cli.org/docs/contributing/). Following them helps to communicate that you respect the time of the other contributors to the project. In turn, they’ll do their best to reciprocate that respect when working with you, across timezones and around the world.
+Read through our [contributing guidelines in the handbook](https://make.wordpress.org/cli/handbook/contributing/) for a thorough introduction to how you can get involved. Following these guidelines helps to communicate that you respect the time of other contributors on the project. In turn, they’ll do their best to reciprocate that respect when working with you, across timezones and around the world.
 
 ## Leadership