Add doc annotations

[tafsiri]

This adds doc annotations to tfjs vis in preparation for hosting its docs on the website.

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This change is 

[nsthorat]

Reviewed 14 of 14 files at r1.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @tafsiri)

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src/visor.ts, line 90 at r1 (raw file):

 */
/**
 * @doc {heading: 'Visor & Surfaces', subheading: 'Visor Methods'}

I think this fits on line line, no need for the multiline jsdoc if you want, also elsewhere

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src/show/model.ts, line 97 at r1 (raw file):

/**
 * @doc {heading: 'Models & Tensors', subheading: 'Model Inspection', namespace:
 * 'show'}

the way I've been doing multiline docs is like:

@doc {
  heading: ...,
  subheading: ...
}

[tafsiri]

Reviewable status: 12 of 14 files reviewed, all discussions resolved (waiting on @nsthorat)

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src/visor.ts, line 90 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

I think this fits on line line, no need for the multiline jsdoc if you want, also elsewhere

Done here and elsewhere

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src/show/model.ts, line 97 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

the way I've been doing multiline docs is like:

@doc {
  heading: ...,
  subheading: ...
}

Done here and elsewhere