docs: update README for 2U fork (#25)

We don't yet publish the docs from our 2U fork to
Read the Docs, so we are temporarily pointing 
directly to docs in GitHub.

The future publishing to Read the Docs for our 
fork is tasked here:
edx/edx-arch-experiments#578

README.rst

@@ -1,60 +1,55 @@
 Devstack
-#################
+########
 
-|ci-provisioning-badge| |ci-cli-badge| |doc-badge| |license-badge|
+|ci-provisioning-badge| |ci-cli-badge| |license-badge|
 |status-badge|
 
 
-DEPRECATION NOTICE
-******************
+Overview
+********
 
-Going forward, devstack will be primarily used for development by 2U. To do development
-on Open edX, it is recommended that `Tutor`_ be used instead.
+This is 2U's version of devstack used for developing using the Open edX platform.
 
-For more information on this deprecation, please visit the `associated deprecation ticket`_.
+The Open edX version of devstack was deprecated and archived. Be careful to
+avoid any outdated documentation from the Open edX Read the Docs or the
+openedx-unsupported GitHub org. For more information on the Open edX
+deprecation, please visit the `associated deprecation ticket`_.
 
-.. _Tutor: https://docs.tutor.edly.io/
 .. _associated deprecation ticket: https://github.com/openedx/devstack/issues/907
 
 
 Getting Started
 ***************
 
-The `Getting Started guide`_ lives with the rest of the documentation in Read the Docs.
+The `Getting Started guide`_ lives with the rest of the documentation.
 
-.. _Getting Started guide: https://edx.readthedocs.io/projects/open-edx-devstack/en/latest/getting_started.html
+.. _Getting Started guide: https://github.com/edx/devstack/blob/master/docs/getting_started.rst
 
 Getting Help
 ************
 
 Documentation
 =============
 
-Start by going through `the documentation`_ on Read the Docs.  If you need more help see below.
+Start by going through `the documentation`_ on GitHub. Our documentation is not yet published
+to Read the Docs, so you should avoid the outdated Open edX docs on Read the Docs.
+If you need more help see below.
 
-.. _the documentation: https://edx.readthedocs.io/projects/open-edx-devstack/en/latest
+.. _the documentation: https://github.com/edx/devstack/tree/master/docs
 
 More Help
 =========
 
-If you're having trouble, we have discussion forums at
-https://discuss.openedx.org where you can connect with others in the
-community.
+If you're having trouble, you can discuss in 2U's `#tech-devstack-questions`_
+Slack channel.
 
-Our real-time conversations are on Slack. You can request a `Slack
-invitation`_, then join our `community Slack workspace`_.
+.. _#tech-devstack-questions: https://twou.slack.com/archives/C04A66RDPEZ
 
 For anything non-trivial, the best path is to open an issue in this
 repository with as many details about the issue you are facing as you
 can provide.
 
-https://github.com/openedx/devstack/issues
-
-For more information about these options, see the `Getting Help`_ page.
-
-.. _Slack invitation: https://openedx.org/slack
-.. _community Slack workspace: https://openedx.slack.com/
-.. _Getting Help: https://openedx.org/getting-help
+https://github.com/edx/devstack/issues
 
 License
 *******
@@ -67,45 +62,21 @@ Please see `LICENSE <LICENSE>`_ for details.
 Contributing
 ************
 
-Contributions are very welcome.
-Please read `How To Contribute <https://openedx.org/r/how-to-contribute>`_ for details.
-
-This project is currently accepting all types of contributions, bug fixes,
-security fixes, maintenance work, or new features.  However, please make sure
-to have a discussion about your new feature idea with the maintainers prior to
-beginning development to maximize the chances of your change being accepted.
-You can start a conversation by creating a new issue on this repo summarizing
-your idea.
-
-The Open edX Code of Conduct
-****************************
-
-All community members are expected to follow the `Open edX Code of Conduct`_.
-
-.. _Open edX Code of Conduct: https://openedx.org/code-of-conduct/
-
-People
-******
-
-**TODO:** Create ``catalog-info.yaml`` for Backstage, and update this section.
+This repository is not open for contributions from outside of 2U.
 
 Reporting Security Issues
 *************************
 
-Please do not report security issues in public. Please email security@openedx.org.
+Please do not report security issues in public. Please email security@edx.org.
 
-.. |ci-provisioning-badge| image:: https://github.com/openedx/devstack/actions/workflows/provisioning-tests.yml/badge.svg?branch=master
-    :target: https://github.com/openedx/devstack/actions/workflows/provisioning-tests.yml
+.. |ci-provisioning-badge| image:: https://github.com/edx/devstack/actions/workflows/provisioning-tests.yml/badge.svg?branch=master
+    :target: https://github.com/edx/devstack/actions/workflows/provisioning-tests.yml
     :alt: CI Provisioning
 
-.. |ci-cli-badge| image:: https://github.com/openedx/devstack/actions/workflows/cli-tests.yml/badge.svg?branch=master
-    :target: https://github.com/openedx/devstack/actions/workflows/cli-tests.yml
+.. |ci-cli-badge| image:: https://github.com/edx/devstack/actions/workflows/cli-tests.yml/badge.svg?branch=master
+    :target: https://github.com/edx/devstack/actions/workflows/cli-tests.yml
     :alt: CI CLI
 
-.. |doc-badge| image:: https://readthedocs.org/projects/open-edx-devstack/badge/?version=latest
-    :target: https://open-edx-devstack.readthedocs.io/en/latest/
-    :alt: Documentation
-
 .. |license-badge| image:: https://img.shields.io/github/license/openedx/devstack.svg
     :target: https://github.com/openedx/devstack/blob/master/LICENSE
     :alt: License