README conversion and translation instruction update (#640)

Convert README to Markdown, and updates translation instructions.

Author: kattni

README.md

@@ -0,0 +1,74 @@
+<a href="https://beeware.org"><img src="http://beeware.org/static/images/brutus-270.png" width="72px" alt="Brutus the Bee"></a>
+
+# beeware.github.io
+
+This is the homepage for the [BeeWare project](http://beeware.org).
+
+It is a [Lektor](https://getlektor.com)-based site.
+
+If you want to contribute a modification, you can fork this repository
+and submit a pull request. However, **do not fork the main branch** -
+fork the [lektor branch](https://github.com/beeware/beeware.github.io/tree/lektor) and make changes there instead.
+
+If you want to test out a change before you submit it, create a virtual
+environment, and install [Lektor](https://getlektor.com):
+
+```
+$ python3 -m venv venv
+$ source venv/bin/activate
+(venv) $ python -m pip install lektor
+```
+
+Then from the root directory of the checkout, run:
+
+```
+(venv) $ lektor server
+```
+
+This will [start a webserver](http://127.0.0.1:5000) that will
+autoreload whenever you make a change to site content.
+
+## Community
+
+You can talk to the community through:
+
+- [@beeware@fosstodon.org on Mastodon](https://fosstodon.org/@beeware)
+- BeeWare Discord server: [Discord](https://beeware.org/bee/chat/)
+- [Tickets on the beeware.github.io issue tracker](https://github.com/beeware/beeware.github.io/issues)
+
+## Contributing
+
+If you find problems with this website, [log them on GitHub](https://github.com/beeware/beeware.github.io/issues). If you want to contribute, please [fork the code](https://github.com/beeware/beeware.github.io/tree/lektor) and [submit a pull request](https://github.com/beeware/beeware.github.io/pulls).
+
+Before submitting a pull request, please make sure your forked branch is
+up-to-date with the original branch. To do this:
+
+- Set your upstream remote:
+
+```
+$ git remote add upstream https://github.com/beeware/beeware.github.io.git
+```
+
+- Make sure you have the latest changes from upstream:
+
+```
+$ git fetch upstream
+```
+
+- Rebase your `lektor` branch to `upstream` before pushing to git
+  and submitting a pull request:
+
+```
+$ git rebase upstream/lektor
+```
+
+## Translations
+
+<a href="https://hosted.weblate.org/projects/beeware/website/"><img src="https://hosted.weblate.org/widget/beeware/website/open-graph.png" width="300px" alt="Website translation status"></a>
+
+We manage translations using [Weblate](https://weblate.org/).
+
+<a href="https://hosted.weblate.org/engage/beeware/"><img src="https://hosted.weblate.org/widget/beeware/website/horizontal-auto.svg" alt="Translation status" /></a>
+
+If you'd like to contribute to the translation effort, join the `#translations`
+channel on [Discord](https://beeware.org/bee/chat/) and introduce yourself!