Add Python 3 support

This change adds support for running this project with Python 3.6. It
adds a new configuration to tox that runs tests against Python 3. It
also modifies the Travis release script so that built wheels are
universal (Python 2 and 3).

.coveragerc

@@ -0,0 +1,11 @@
+[run]
+source =
+    ccdb5_ui
+
+omit = 
+    */wsgi.py
+
+[report]
+exclude_lines = 
+    pragma: no cover
+    if __name__ == .__main__.:

.travis.yml

@@ -1,17 +1,18 @@
 ---
-language: node_js
+language: python
 python:
-  - "2.7"
+  - 2.7
+  - 3.6
 install:
-  - pip install --user tox
+  - pip install tox-travis
 script:
   # The tox tests run the frontend build so no manual npm install is needed.
   - tox
   - npm test
   # We don't want changes to package-lock.json to show up as local git
   # changes when the Python wheel tag is determined.
   - git checkout package-lock.json
-  - python setup.py bdist_wheel
+  - python setup.py bdist_wheel --universal
 after_script:
   - cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js
 deploy:

setup.py

@@ -32,6 +32,7 @@ def read_file(filename):
         'Intended Audience :: Developers',
         'Programming Language :: Python',
         'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3.6',
         'Framework :: Django',
         'Development Status :: 4 - Beta',
         'Operating System :: OS Independent',

tox.ini

@@ -1,11 +1,17 @@
 [tox]
 skipsdist=True
-
-envlist=dj{111}
+envlist=py{27,36}-dj{111}
 
 [testenv]
 install_command=pip install -e ".[testing]" -U {opts} {packages}
-commands=coverage run ./manage.py test
+commands=
+    coverage erase
+    coverage run ./manage.py test
+    coverage report --skip-covered
+
+basepython=
+    py27: python2.7
+    py36: python3.6
 
 deps=
     coverage==4.5.1