add new molecule scenario, add tox config

tox.ini

@@ -0,0 +1,14 @@
+[tox]
+minversion = 1.8
+basepython = python3.6
+envlist = py{37,39}-ansible{210,30}
+skipsdist = true
+
+[testenv]
+passenv = *
+deps =
+    -r tox-requirements.txt
+    ansible210: ansible<3.0
+    ansible30: ansible<3.1
+commands =
+    {posargs:molecule test -s podman}