Support ES6 data structure visualization

[roblourens]

P1, 3 days
Currently we can't show the items in a Map or Set.

[roblourens]

Need to look at the internalProperties of the object, and merge it into its collected properties. Looks like

{
    "id": 20,
    "result": {
        "result": [
            {
                "name": "__proto__",
                "value": {
                    "type": "object",
                    "className": "Map",
                    "description": "Map",
                    "objectId": "{\"injectedScriptId\":1,\"id\":62}"
                },
                "writable": true,
                "configurable": true,
                "enumerable": false,
                "isOwn": true
            }
        ],
        "internalProperties": [
            {
                "name": "[[Entries]]",
                "value": {
                    "type": "object",
                    "subtype": "array",
                    "className": "Array",
                    "description": "Array[1]",
                    "objectId": "{\"injectedScriptId\":1,\"id\":63}"
                }
            }
        ]
    }
}