simplify tox config

Author: st4lk

tox.ini

@@ -1,60 +1,27 @@
 [tox]
 envlist=
-    py34-16
-    py34-17
-    py34-18
-    py27-16
-    py27-17
-    py27-18
+    py{27,34}-django{16,17,18},
 
 [testenv]
 setenv =
     PYTHONPATH = {toxinidir}/example/web_project
     LC_ALL = en_US.utf-8
+basepython =
+    py27: python2.7
+    py34: python3.4
 deps =
     django-crispy-forms==1.4.0
     Pillow
+    django16: Django>=1.6,<1.7
+    django16: south
+    django17: Django>=1.7,<1.8
+    django18: Django>=1.8,<1.9
+    py27-django18: coverage
     -rrequirements_test.txt
 commands =
     py.test
 
-[testenv:py34-16]
-basepython = python3.4
-deps =
-    south
-    django<1.7
-    {[testenv]deps}
-
-[testenv:py34-17]
-basepython = python3.4
-deps =
-    django<1.8
-    {[testenv]deps}
-
-[testenv:py34-18]
-basepython = python3.4
-deps =
-    django<1.9
-    {[testenv]deps}
-
-[testenv:py27-16]
-basepython = python2.7
-deps =
-    south
-    django<1.7
-    {[testenv]deps}
-
-[testenv:py27-17]
-basepython = python2.7
-deps =
-    django<1.8
-    {[testenv]deps}
-
 [testenv:py27-18]
-basepython = python2.7
-deps =
-    django<1.9
-    {[testenv]deps}
 commands =
     coverage run --source=affiliate --omit=*migrations* -m py.test
     coverage report