add pypy3 target to travis builds

Author: miguelgrinberg

.travis.yml

@@ -13,6 +13,8 @@ matrix:
           env: TOXENV=py36
         - python: pypy
           env: TOXENV=pypy
+        - python: pypy3
+          env: TOXENV=pypy3
         - python: 3.6
           env: TOXENV=docs
 install:

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist=flake8,py27,py34,py35,py36,pypy,docs,coverage
+envlist=flake8,py27,py34,py35,py36,pypy,pypy3,docs,coverage
 skip_missing_interpreters=True
 
 [testenv]
@@ -16,6 +16,7 @@ basepython =
     py35: python3.5
     py36: python3.6
     pypy: pypy
+    pypy3: pypy3
 
 [testenv:flake8]
 basepython=python3.6