feat(tox): add basic tox.ini

MANIFEST.in

 include README.rst
 include *.py
 include */*.py
+include *.ini
 
 recursive-include cubicweb_ckeditor *.py
 recursive-include cubicweb_ckeditor/data *.gif *.png *.ico *.css *.js

tox.ini

+[tox]
+envlist = py27, py3, flake8, check-manifest, safety
+
+[testenv]
+deps =
+  git+https://github.com/psycojoker/pytest-capture-deprecatedwarnings
+  pytest
+  unittest2
+commands =
+  {envpython} -m pytest {posargs:{toxinidir}/test}
+
+[testenv:flake8]
+basepython = python3
+skip_install = true
+deps =
+  flake8
+commands = {envpython} -m flake8 {toxinidir} {posargs}
+
+[testenv:check-manifest]
+skip_install = true
+deps =
+  check-manifest
+commands =
+  {envpython} -m check_manifest {toxinidir}
+
+[flake8]
+basepython = python3
+format = pylint
+ignore = W503, E203, E731, E231
+max-line-length = 100
+exclude = cubicweb_ckeditor/migration/*,docs/*,.tox/*,./test/data/*
+
+[testenv:safety]
+deps =
+    safety
+commands =
+    safety check
\ No newline at end of file