Django>=2.0 support

[makinacorpus]

Django>=2.0 support

[Gagaro]

Hi,

I would have time to do that only if I work on a project which would require it. Which won't be the case before a long time.

I'd gladly review and merge a PR doing it though.

[Gagaro]

I added the 2.0 testing in travis: https://travis-ci.org/makinacorpus/django-safedelete

If it is just an issue with the import, I'll fix it and release it.

[Gagaro]

But I'd have to fix #90 first.

[airctobot]

I have updated the test-cases: #93 seems to be working fine with Django 2.0

[Gagaro]

The tests are green with Django 2.0 (thanks @ds-ac !). If you still have issues, you can open a new issue, or even better, a PR with a failing test.

[Gagaro]

0.4.5 has been released with the support for Django 2.0

[Euphorbium]

Could update the docs and mention that this in fact does support django 2?

[Gagaro]

Yes, thanks for the heads up.