Add now mandatory readthedocs config file

Also:
- Remove unnecessary and now unresolvable python-lzo doc requirement

.readthedocs.yaml

@@ -0,0 +1,27 @@
+# Read the Docs configuration file for Sphinx projects
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Set the OS, Python version and other tools you might need
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.12"
+
+# Build documentation in the "docs/" directory with Sphinx
+sphinx:
+  configuration: doc/source/conf.py
+
+# Optionally build your docs in additional formats such as PDF and ePub
+# formats:
+#   - pdf
+
+# Optional but recommended, declare the Python requirements required
+# to build your documentation
+# See https://docs.readthedocs.io/en/stable/guides/reproducible-builds.html
+python:
+  install:
+    - path: .
+    - requirements: doc/requirements.txt

doc/requirements.txt

@@ -1,2 +1 @@
-https://bitbucket.org/james_taylor/python-lzo-static/get/63987d89fd1b.zip
 numpy