adding yaml config for docs compilation

docs/.readthedocs.yml

@@ -0,0 +1,20 @@
+version: 2
+
+# Build documentation in the docs/ directory with Sphinx
+sphinx:
+  configuration: docs/conf.py
+
+# Build all formats
+formats: all
+
+python:
+   version: 3.7
+   install:
+      - requirements: docs/requirements.txt
+      - method: pip
+        path: .
+        extra_requirements:
+            - docs
+      - method: setuptools
+        path: another/package
+   system_packages: true