Move explicit tensorflow dependency from CI config to tox config

Author: ludwigschubert

.travis.yml

@@ -5,7 +5,6 @@ python:
 install:
   - pip install -U pip wheel
   - pip install python-coveralls
-  - pip install tensorflow
   - pip install tox-travis
 script:
   - tox

setup.py

@@ -24,8 +24,8 @@
 
 extras = {
     "test": test_deps,
-    "tf": ["tensorflow>=1.0.0"],
-    "tf_gpu": ["tensorflow-gpu>=1.0.0"],
+    "tf": ["tensorflow>=1.6.0"],
+    "tf_gpu": ["tensorflow-gpu>=1.6.0"],
 }
 
 setup(

tox.ini

@@ -2,7 +2,9 @@
 envlist = py{27,36}
 
 [testenv]
-deps = .[test]
+deps =
+  tensorflow
+  .[test]
 commands = coverage run --source lucid -m py.test
 
 [pytest]