Bump version to 0.15.3 (tensorflow#1572)

Bump version to 0.15.3

Update core to 1.0.0-alpha3 (tensorflow#1565)

INTERNAL

0.15.x: Update to 0.15.2. (tensorflow#1567)

INTERNAL

Update core at master to 1.0.0-alpha2 (tensorflow#1552)

DEV

Update 0.15.x to 0.15.1. (tensorflow#1551)

Always test for a fence with gl2.clientWaitSync(sync, 0, 0) (tensorfl…

…ow#1529)

Fixes tensorflow/tfjs#1145

The smallest repro is calling .data() 3 times without waiting:
```ts
tf.ENV.set('WEBGL_CPU_FORWARD', false)
tf.ENV.set('WEBGL_SIZE_UPLOAD_UNIFORM', 0);
tf.square(3).data();
tf.square(3).data();
tf.square(3).data();
```

There are 3 fences that are in parallel. And on the next tick the binary search tests only the middle fence and sees that it is done, and assumes the first fence is done too. But since we never explicitly tested fence[0].isDone(), Chrome gives a warning.

The warnings started showing up more often when Layers started doing parallel reads of the scalar loss values: tensorflow/tfjs-layers#398

I changed the binary search to linear search so we also test all fences up to the one that is not done.

Update to 0.15.0 and update the publish npm script to allow the relea…

…se branch. (tensorflow#1514)

Fix derivative of PRELU when alpha gets broadcasted and bump version …

…to 0.14.5 (tensorflow#1487)

BUG
Fix derivative of PRELU when alpha gets broadcasted and update patch version

h/t to @caisq for finding the bug.

Bump version to 0.14.4 (tensorflow#1478)

INTERNAL

Bump version: 0.14.2 --> 0.14.3 (tensorflow#1467)