install as travis user

Author: javierluraschi

.travis.yml

@@ -20,9 +20,9 @@ before_script:
   - pip2.7 install --upgrade --ignore-installed --user travis virtualenv
   - pip2.7 install --upgrade --ignore-installed --user travis keras h5py pyyaml requests Pillow scipy theano
   - if [[ $TENSORFLOW_VERSION == "1.12" ]]; then
-      pip2.7 install https://storage.googleapis.com/tensorflow/linux/cpu/tensorflow-1.12.0-cp27-none-linux_x86_64.whl
+      pip2.7 install --upgrade --ignore-installed --user travis https://storage.googleapis.com/tensorflow/linux/cpu/tensorflow-1.12.0-cp27-none-linux_x86_64.whl
     else
-      pip2.7 install tensorflow
+      pip2.7 install --upgrade --ignore-installed --user travis tensorflow
     fi
   - pip show tensorflow