* port hash_password

* changelog

It seems that, at some point, the ability to run tox on old servers (with old
setuptools) got broken - and it was only working on our Jenkins instance by
dint of reusing the tox environments.

Let's try to get tox to do the right thing, and remove the guff from
jenkins/prepare_synapse.sh.

(There is a separate question about whether the jenkins builds should be using
tox to prepare the virtualenv at all here, but that is somewhat orthogonal).

I don't think we ever use this, and it slows things down. If we want to use it,
we should just do so on a couple of builds rather than all of them.

Signed-Off-By: Matthias Kesler <krombel@krombel.de>

Signed-off-by: Adrian Tschira <nota@notafile.com>

add missing comma

It's just a few tests, but it will at least prevent a few files from
regressing. Also, it makes it easiert to check your code against py36
while writing it.

Signed-off-by: Adrian Tschira <nota@notafile.com>

- this ensures we end up with a working virtualenv which we can use for other
things.

We now need to set PYTHONPATH when running the unit tests; update tox config to
do so.

No features of Bash are used here, so using /bin/sh makes it more portable to systems that don't have Bash natively (like BSD systems).

Outputs:
 * results.xml
 * coverage.xml
 * violations.flake8.log

`tox` will run all tests
`tox tests.api.test_auth.AuthTestCase` will run just the tests in AuthTestCase