Fix gcs_test issues

1) pip install issue related to recent numpy upgrade
2) OutOfRange package issue caused by recent changes in TF Python code

tensorflow/tools/gcs_test/Dockerfile

-FROM ubuntu:14.04
+FROM ubuntu:16.04
 
 MAINTAINER Shanqing Cai <cais@google.com>
 

tensorflow/tools/gcs_test/python/gcs_smoke.py

@@ -107,6 +107,6 @@ if __name__ == "__main__":
         print("FAIL: Failed to catch the expected OutOfRangeError while "
               "reading one more record than is available")
         sys.exit(1)
-      except tf.python.framework.errors.OutOfRangeError:
+      except tf.errors.OutOfRangeError:
         print("Successfully caught the expected OutOfRangeError while "
               "reading one more record than is available")