Add .readthedocs.yml

.readthedocs.yml

@@ -0,0 +1,15 @@
+requirements_file: requirements/docs.txt
+
+build:
+  image: latest
+
+python:
+  version: 3.6
+  setup_py_install: false
+  pip_install: true  # need this for correct pyproject.toml handling
+  extra_requirements:
+    - validation
+
+# extra formats in addition to the default HTML web docs
+formats:
+    - pdf

.travis.yml

@@ -15,11 +15,10 @@ jobs:
       python: '3.7'
       dist: xenial
       sudo: required
+    - python: '3.6'
+    env: TOXENV=docs
     - python: '3.6'
       env: TOXENV=djmaster
-    - # readthedocs uses python 3.5 for building
-      python: '3.5'
-      env: TOXENV=docs
     - python: '3.6'
       env: TOXENV=lint