message: Fix error when loading s3 file system library.
  If attempting to call tf.load_file_system_library on the S3 library you
  would previously get an error similiar to...
  s3_file_system.so: undefined symbol: _ZN5nsync13nsync_mu_lockEPNS_11nsync_mu_s_E
  Changing the build rule to be tf_cc_binary instead of cc_binary fixes this issue.
diff: @@ -9,6 +9,7 @@ exports_files(["LICENSE"])
  load(
  "//tensorflow:tensorflow.bzl",
  + "tf_cc_binary",
  "tf_cc_test",
  )
  @@ -24,7 +25,7 @@ filegroup(
  visibility = ["//tensorflow:__subpackages__"],
  )
  -cc_binary(
  +tf_cc_binary(
  name = "s3_file_system.so",
  srcs = [
  "s3_crypto.cc",
  