Add some basic content to readmes

Part of migration from wiki.eclipse.org
Part of eclipse-simrel#5

README.md

@@ -1 +1,8 @@
-# .github
+# GitHub Profile and Wiki for Eclipse SimRel
+
+This repository contains the profile files for the Eclipse SimRel organization and the wiki pages.
+
+Please see these key pages for more information:
+
+- [Main entry point](https://github.com/eclipse-simrel)
+- [wiki pages](./wiki)

wiki/README.md

@@ -0,0 +1,18 @@
+# Eclipse IDE Simultaneous Release (SimRel)
+
+The [Eclipse Foundation](https://wiki.eclipse.org/Foundation) and its community of projects and contributors produce releases on a coordinated schedule that are often referred to as *simultaneous release*, *coordinated release* or *release train* of Eclipse.
+
+This folder provides the "wiki" for the Eclipse SimRel and Eclipse Planning Council.
+The main pages on this wiki are:
+
+- [Eclipse Simultaneous Release](Simultaneous_Release.md)
+- [Eclipse Planning Council](Planning_Council.md)
+
+Pull requests are welcome for these pages.
+
+#### Why this format?
+
+You may be wondering why this format for the pages?
+The information in this folder used to be stored at [wiki.eclipse.org](https://wiki.eclipse.org/), but in early 2024 that wiki [will be made read-only](https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/wikis/Wiki-shutdown-plan).
+The GitHub built-in wiki was determined to be insufficient (non-committers can't easily contribute - no PRs, folder nesting is not fully supported and overall navigation is somewhat limited), therefore simply storing the files as markdown directly in this repository seemed the best solution.
+Contributions that turn these markdown files into HTML, using technology like Jekyll and GitHub pages would be very welcome.