Make tests run all once (now with docs).

.travis.yml

@@ -1,22 +1,8 @@
 language: python
-python:
+
-  - "2.7"
-  - "3.4"
-  - "3.5"
-  - "3.6"
-env:
-  - DJANGO=1.8
-  - DJANGO=1.9
-  - DJANGO=1.10
-  - DJANGO=1.11
-  - DJANGO=2.0
-matrix:
-  exclude:
-    - python: "2.7"
-      env: DJANGO=2.0
 install:
   - pip install tox coveralls
 script:
-  - tox -e py${TRAVIS_PYTHON_VERSION//[.]/}-django${DJANGO//[.]/}
+  - tox
 after_success:
   - coveralls

tox.ini

@@ -1,5 +1,6 @@
 [tox]
 envlist=
+    docs,
     py27-django{18,19,110,111},
     py34-django{18,19,110,111,20},
     py35-django{18,19,110,111,20},
@@ -27,6 +28,8 @@ commands =
 [testenv:docs]
 basepython = python2.7
 changedir = docs
+whitelist_externals =
+    mkdir
 deps =
     sphinx
     sphinx_rtd_theme