Python 3.7 support

[revmischa]

3.7 has been out

https://travis-ci.org/ambv/flake8-mypy/jobs/397937231 builds fail

/home/travis/build/ambv/flake8-mypy/tests/test_mypy.py:30:1: T499 mypy: error: failed to find a Python executable matching version (3, 6), perhaps try --python-executable, or --no-site-packages?

I also get this same error when running my own tests on travis xenial with 3.7:

 FLAKE8-check(ignoring E402 E305 E501 I201 I101 I100 D204 D101 E722 D401 D413 D300 D106) 
[gw0] linux -- Python 3.7.0 /home/travis/virtualenv/python3.7.0/bin/python
/home/travis/build/jetbridge/backend/jetbridge/jbflask.py:1:1: T499 usage: mypy [-h] [-v] [-V] [more options; see below]
/home/travis/build/jetbridge/backend/jetbridge/jbflask.py:2:1: T499             [-m MODULE] [-p PACKAGE] [-c PROGRAM_TEXT] [files ...]
/home/travis/build/jetbridge/backend/jetbridge/jbflask.py:3:1: T499 mypy: error: failed to find a Python executable matching version (3, 6), perhaps try --python-executable, or --no-site-packages?

[eedwards-sk]

I'm running into the same issue with vscode and simple linting.

[revmischa]

Try #22

[MRigal]

I guess this is now fixed on master! What about a new version @ambv ?

[revmischa]

new release would be nice

[MRigal]

You can't trigger a new release @revmischa ? Only @ambv can do that?

It's really annoying that it's not possible to use it on Python 3.7 for example...

[revmischa]

I can't, sorry
I'm using flake8-mypy = {ref = "27f1888d7e6766d1b4357cb7a2ecede4bc95b281",git = "https://github.com/jetbridge/flake8-mypy.git"}