Add image.transform.

[lina128]

Add tf addon equivalent image.transform to tfjs (https://www.tensorflow.org/addons/api_docs/python/tfa/image/transform). Helpful for many image processing tasks. This PR only implemented for the cpu and webgl backend.

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This change is 

[pyu10055]

Thanks, this would be very useful for image processing pipeline.

Reviewable status: 0 of 1 approvals obtained (waiting on @lina128)

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tfjs-backend-cpu/src/kernels/Transform.ts, line 226 at r1 (raw file):

  // f(x, yFloor) = (xCeil - x) / (xCeil - xFloor) * f(xFloor, yFloor)
  //               + (x - xFloor) / (xCeil - xFloor) * f(xCeil, yFloor)
  const valueYFloor =

good to name it valueXYFloor and valueXYCeil, since it is interpolating for x

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tfjs-core/src/ops/image/transform.ts, line 32 at r1 (raw file):

 *
 * @param image 4d tensor of shape `[batch, imageHeight, imageWidth, depth]`.
 * @param transforms Projective transform matrix/matrices. A vector of length

we don't use the term vector, probably call it tensor1d ?

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tfjs-core/src/ops/image/transform_test.ts, line 21 at r1 (raw file):

import {expectArraysClose} from '../../test_util';

describeWithFlags('image.transform', BROWSER_ENVS, () => {

it would be good to add test for different fill and interpolation modes

[pyu10055]

Reviewed 11 of 11 files at r1.
Reviewable status: 0 of 1 approvals obtained (waiting on @lina128)

[pyu10055]

Reviewed 2 of 2 files at r2.
Reviewable status: complete! 1 of 1 approvals obtained (waiting on @lina128)