Remove Python 3.7 from both tox and travis config files. Apparently the Travis + Tox combo doesn't get along very well with Python 3.7 just yet

Author: JavierLuna

.travis.yml

@@ -1,10 +1,8 @@
 language: python
 python:
     - '3.6'
-    - '3.7-dev'
 install:
   - pip install pipenv
-  - pipenv install --dev
   - pip install -U tox coveralls
 
 script:

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py36,py37
+envlist = py36
 
 [testenv]
 commands =
@@ -17,15 +17,6 @@ whitelist_externals = /bin/bash
 [testenv:py36]
 basepython = python3.6
 deps = pipenv
-commands=
-    pipenv install --dev --ignore-pipfile
-    python setup.py test
-setenv=
-    LC_ALL=en_GB.UTF-8
-    LANG=en_GB.UTF-8
-[testenv:py37]
-basepython = python3.7
-deps = pipenv
 commands=
     pipenv install --dev --ignore-pipfile
     python setup.py test