tensorboard 2.0.0 on Python PyPI

The 2.0 minor series tracks TensorFlow 2.0.

Breaking changes

TensorBoard now serves on localhost only by default to avoid unintentional
overexposure. To expose TensorBoard to the network, either use a proxy, bind
to a specific hostname or IP address by using the --host flag, or explicitly
enable the previous behavior of binding on all network interfaces by passing
the flag --bind_all. See PR #2589.
The --logdir flag no longer supports passing multiple comma-delimited paths,
which means that it now supports paths containing literal comma and colon
characters, like ./logs/m=10,n=20,lr=0.001 or ./logs/run_12:30:15. To
mimic the old behavior, prefer using a tree of symlinks as it works with more
plugins, but as a fallback the flag --logdir_spec exposes the old behavior.
See PR #2664.
Projector plugin visualize_embeddings() API now takes logdir as its first
parameter rather than writer (which only supported TF 1.x summary writers).
For backwards compatibility TF 1.x writers will still be accepted, but passing
the logdir explicitly is preferred since it works without any dependency on
TF 1.x or 2.x summary writing. See PR #2665.
The namespace tensorboard.summary.* now aliases the summary API symbols in
tensorboard.summary.v2.* rather than those in tensorboard.summary.v1.*.
The old symbols can still be accessed under the .v1 names. Note that the
new v2 API symbols are exposed in TF 2.0 as the new tf.summary.* API and
this is normally how they should be used. See PR #2670.

Smarter log directory polling can be used by passing --reload_multifile=true
to poll all "active" event files in a directory rather than only the last one.
This avoids problems where data written to the non-last file never appears.
See PR #1867 for details, including how to adjust the "active" threshold.
What-If Tool now can sort PD plots by interestingness (#2461)