Configure Read The Docs in the repository

Also updates the MkDocs `pages:` setting to `nav:`, which appears to have replaced it in later versions.

Author: mpilgrem

.readthedocs.yaml

@@ -0,0 +1,20 @@
+# .readthedocs.yaml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Set the version of Python and other tools you might need
+build:
+  os: ubuntu-20.04
+  tools:
+    python: "3.9"
+
+mkdocs:
+  configuration: mkdocs.yml
+
+# Optionally declare the Python requirements required to build your docs
+python:
+   install:
+   - requirements: doc/requirements.txt

doc/requirements.txt

@@ -0,0 +1,13 @@
+# pip requirements file for MkDocs, used by Read The Docs
+#
+# See:
+#
+# The Read The Docs recommendation to 'pin' the MkDocs version used to build
+# documentation:
+# https://docs.readthedocs.io/en/stable/guides/reproducible-builds.html#pinning-dependencies
+#
+# The pip guide to its requirements file format:
+# https://pip.pypa.io/en/stable/reference/requirements-file-format/
+#
+# Latest version of MkDocs as at 2 August 2022
+mkdocs==1.3.1

mkdocs.yml

@@ -12,7 +12,7 @@ extra_css:
 extra_javascript:
 - js/searchhack.js
 
-pages:
+nav:
 - Home: README.md
 - Changelog: ChangeLog.md
 - Tool documentation: