docs: Add config file for readthedocs

This moves away from web-based settings and permits per-release
changes.

diff --git a/.readthedocs.yaml b/.readthedocs.yaml
new file mode 100644 (file)
index 0000000..bae5551
--- /dev/null
+++ b/.readthedocs.yaml
@@ -0,0 +1,17 @@
+version: 2
+
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.8"
+
+sphinx:
+  configuration: docs/conf.py
+
+formats:
+  - pdf
+  - epub
+
+python:
+  install:
+    - requirements: docs/requirements.txt