Fixed #22446 -- Added tox.ini to automate pull request checks.

tox.ini

@@ -0,0 +1,69 @@
+# Tox (http://tox.testrun.org/) is a tool for running tests in multiple
+# virtualenvs. This configuration file helps to run the test suite on all
+# supported Python versions. To use it, "pip install tox" and then run "tox"
+# from this directory.
+
+[tox]
+skipsdist = true
+envlist =
+    py3
+    flake8
+    docs
+    isort
+
+# Add environments to use default python2 and python3 installations
+[testenv:py2]
+basepython = python2
+
+[testenv:py3]
+basepython = python3
+
+[testenv]
+usedevelop = true
+passenv = DJANGO_SETTINGS_MODULE
+deps =
+    py{2,27}: -rtests/requirements/py2.txt
+    py{3,34,35}: -rtests/requirements/py3.txt
+    postgres: -rtests/requirements/postgres.txt
+    mysql: -rtests/requirements/mysql.txt
+    oracle: -rtests/requirements/oracle.txt
+changedir = tests
+commands =
+    {envpython} runtests.py {posargs}
+
+[testenv:flake8]
+basepython = python3
+usedevelop = false
+deps = flake8
+changedir = {toxinidir}
+commands = flake8 .
+
+[testenv:docs]
+# On OS X, as of pyenchant 1.6.6, the docs build only works under Python 2.
+basepython = python2
+usedevelop = false
+whitelist_externals =
+    make
+deps =
+    Sphinx
+    pyenchant
+    sphinxcontrib-spelling
+changedir = docs
+commands =
+    make spelling
+
+[testenv:isort]
+basepython = python3
+usedevelop = false
+deps = isort
+changedir = {toxinidir}
+commands = isort --recursive --check-only --diff django tests scripts
+
+[testenv:javascript]
+usedevelop = false
+deps =
+changedir = {toxinidir}
+whitelist_externals = npm
+commands =
+    npm install
+    npm test