Option to show quotes around strings

The API we work with returns a JSON with a bunch of fields. Sometimes it deals with numbers that may be sent as a string, especially where the number of digits (and any leading zeroes) are important to be preserved.

For example, there are cases where an ID needs to be 5 characters so a 4-digit ID is sent as "01234". But the UI makes it hard to know whats a string and what's a number because neither are quoted.

```json
{
"num_id": 1234,
"str_id": "01234",
}
```

is rendered as

It would be nice if there was an option to show quotes for string values in the tree UI.