Object Detection to Core ML

> Please provide us with the following information:
> ---------------------------------------------------------------

### This issue is for a: (mark with an `x`)
```
- [ ] bug report -> please search issues before submitting
- [ ] feature request
- [x] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
```

### Minimal steps to reproduce
>

### Any log messages given by the failure
>

### Expected/desired behavior
>

### OS and Version?
> Windows 7, 8 or 10. Linux (which distribution). macOS (Yosemite? El Capitan? Sierra?)
iOS 12

### Versions
>

### Mention any other details that might be useful

> ---------------------------------------------------------------
I trained an object detection model from Custom Vision export to CoreML format. And the model output multidimensional array of doubles. And I don't know how to get the tagId, tagName, probability & bounding box? Are there any document or example to show how to do it? Thanks.

The issue names no file or test. Start by reviewing the sample's iOS Core ML model-inference flow and the multidimensional output from a Custom Vision object-detection export; document how tagId, tagName, probability, and bounding boxes are obtained, with an example, and verify it against an object-detection model.

Written by the indexing model from the issue text.