Merge pull request #708 from rstudio/bugfix/update-travis-1.13

add nightly; update 2.0 preview URL

Author: javierluraschi

.travis.yml

@@ -22,15 +22,23 @@ matrix:
       env:
         - KERAS_IMPLEMENTATION="tensorflow"
         - TENSORFLOW_WHEEL="https://storage.googleapis.com/tensorflow/linux/cpu/tensorflow-1.12.0-cp27-none-linux_x86_64.whl"
+    - name: "nightly"
+      env:
+        - TENSORFLOW_VERSION="nightly"
+        - TENSORFLOW_PYTHON="/usr/bin/python3"
     - name: "TensorFlow (TensorFlow 2.0-preview)"
       env:
         - KERAS_IMPLEMENTATION="tensorflow"
-        - TENSORFLOW_WHEEL="https://files.pythonhosted.org/packages/b8/48/983c8af6e63cfeebb6bb89866c38ea7d16491b8f72309f27df41b33a751e/tf_nightly_2.0_preview-1.13.0.dev20190117-cp27-cp27mu-manylinux1_x86_64.whl"
+        - TENSORFLOW_WHEEL="https://files.pythonhosted.org/packages/ba/98/b0b9b83c9eddb9a112e0f928481c78232e1675397ccc717d1dcd92b8544b/tf_nightly_2.0_preview-2.0.0.dev20190319-cp27-cp27mu-manylinux1_x86_64.whl"
   allow_failures:
+    - name: "nightly"
+      env:
+        - TENSORFLOW_VERSION="nightly"
+        - TENSORFLOW_PYTHON="/usr/bin/python3"
     - name: "TensorFlow (TensorFlow 2.0-preview)"
       env:
         - KERAS_IMPLEMENTATION="tensorflow"
-        - TENSORFLOW_WHEEL="https://files.pythonhosted.org/packages/b8/48/983c8af6e63cfeebb6bb89866c38ea7d16491b8f72309f27df41b33a751e/tf_nightly_2.0_preview-1.13.0.dev20190117-cp27-cp27mu-manylinux1_x86_64.whl"
+        - TENSORFLOW_WHEEL="https://files.pythonhosted.org/packages/ba/98/b0b9b83c9eddb9a112e0f928481c78232e1675397ccc717d1dcd92b8544b/tf_nightly_2.0_preview-2.0.0.dev20190319-cp27-cp27mu-manylinux1_x86_64.whl"
 
 cache:
   packages: true