travis: add stubtest_test to CI

Author: hauntsaninja

.travis.yml

@@ -29,3 +29,19 @@ jobs:
     - name: "flake8"
       install: pip install -r requirements-tests-py3.txt
       script: flake8
+    - name: "stubtest py38"
+      python: 3.8
+      install: pip install -U git+git://github.com/python/mypy@a07dbd00
+      script: ./tests/stubtest_test.py
+    - name: "stubtest py37"
+      python: 3.7
+      install: pip install -U git+git://github.com/python/mypy@a07dbd00
+      script: ./tests/stubtest_test.py
+    - name: "stubtest py36"
+      python: 3.6
+      install: pip install -U git+git://github.com/python/mypy@a07dbd00
+      script: ./tests/stubtest_test.py
+    - name: "stubtest py35"
+      python: 3.5
+      install: pip install -U git+git://github.com/python/mypy@a07dbd00
+      script: ./tests/stubtest_test.py