Trying to figure out travis build stages

.travis.yml

@@ -1,32 +1,33 @@
+# stage: test supported Python versions
+sudo: false
+language: python
+python:
+  - 2.7
+  - 3.4
+  - 3.5
+  - 3.6
+  - pypy
+  - pypy3
+
+install:
+  - pip install -U setuptools pip sphinx tox tox-travis
+
+script:
+  - ./bin/test_standalone.sh
+  - tox
+  - ./bin/check_readme.sh
+
+branches:
+  except:
+    - standalone
+
 jobs:
   include:
-    - stage: test supported Python versions
-      sudo: false
-      language: python
-      python:
-        - 2.7
-        - 3.4
-        - 3.5
-        - 3.6
-        - pypy
-        - pypy3
-
-      install:
-        - pip install -U setuptools pip sphinx tox tox-travis
-
-      script:
-        - ./bin/test_standalone.sh
-        - tox
-        - ./bin/check_readme.sh
-
-      branches:
-        except:
-          - standalone
 
     - stage: test Docker image
-      language: python
       sudo: required
       services:
         - docker
+      install: []
       scirpt:
         - bin/test-docker.sh