Merge pull request #3 from manics/readme

Add RTD link to README

README.md

@@ -2,3 +2,31 @@
 
 [![Build](https://github.com/manics/rse-tre/actions/workflows/build.yml/badge.svg)](https://github.com/manics/rse-tre/actions/workflows/build.yml)
 [![Documentation Status](https://readthedocs.org/projects/rse-tre-community/badge/?version=latest)](https://rse-tre-community.readthedocs.io/en/latest/?badge=latest)
+
+https://rse-tre-community.readthedocs.io/
+
+## Overview
+
+This repository is published using [Read the Docs](https://rse-tre-community.readthedocs.io/).
+The documentation is built with Sphinx, and written in [Markdown with the MyST Parser](https://myst-parser.readthedocs.io/).
+
+To build this repository locally, create a Python environment and install the requirements:
+
+```sh
+cd docs
+pip install -r requirements.txt
+```
+
+Then build the documentation:
+
+```sh
+make html
+```
+
+[pre-commit](https://pre-commit.com/) is used to check the documentation for common issues, and to auto-format all content.
+
+To run pre-commit locally:
+
+```sh
+pre-commit run --all-files
+```