Bump T2T to 1.15.7

PiperOrigin-RevId: 316843874

[T2T] Bump version to 1.15.6

PiperOrigin-RevId: 314329134

Bump T2T version to 1.15.5

With this change Travis will turn green.

When we import compat.v1, we shouldn't do tf.compat.v1 anymore.

Also the following to unclog Travis:
six>=1.12.0 is required by tf-hub 0.8.0, one of the core dependencies seems to
be installing tf-hub, so pinning tf-hub to 0.7.0 (which is in the extras
section) doesn't seem to help.

Locally the previous setup.py installs fine, but only errors on Travis for some
reason.

PiperOrigin-RevId: 307203166

Bump up version to 1.15.4

PiperOrigin-RevId: 289189869

In files where we explicitly import tf.compat.v1, don't qualify acces…

…s of tf.compat.v1 again.

PiperOrigin-RevId: 289135863

Changes needed for T2T's problems to be imported on TF 2.0 -- this do…

…esn't mean we are using these problems.

This is only so that we can `import trax` on these environments.

PiperOrigin-RevId: 282108974

Move from tf flags to absl flags, since they seem to be gone in tf 1.15

NOTE: This is only for libraries (and not binaries) in data_generators/

Also bump up version to 1.15.1

Also add a description to show on PyPI

PiperOrigin-RevId: 282056584

pip installing tensorflow serving seems to be uninstalling the installed

version of tensorflow (1.15.0) and replacing with 2.0, leading to errors of
missing contrib -- so install a pinned version.

Make an error in all_problems.py log earlier.

Reverting the earlier change about tf flags not being shipped with TF, because of this TF 2.0 subterfuge.

PiperOrigin-RevId: 281893644

Execute `jupyter nbconvert` on python3 instead of python2.

python2 fails with:
`RuntimeError: Kernel died before replying to kernel_info`

python3 seems to pass.

PiperOrigin-RevId: 272718077

Bump version to 1.14.0

PiperOrigin-RevId: 264699622