(de)Serialization

[TheMarksman]

It would be nice if there were a canonical representation of the constraints:

{
    "constraints": {
        "box:a/right#": {
            "op": "eq",
            "left": "box:a#right",
            "right": ["box:a#left", "box:a#width"]
        },
        "box:a/bottom#": {
            "op": "eq",
            "left": "box:a#bottom",
            "right": ["box:a#top", "box:a#height"]
        },
        "box:a/left#": {
            "op": "eq",
            "left": "box:a#left",
            "right": 10
        },
        "box:a/top#": {
            "op": "eq",
            "left": "box:a#top",
            "right": [10, [0.5, "box:a/width"]]
        }
    }
}

with an api like this:

var k3 = K3()
    // add some constraints
    .json(seralized);

// manually add some constraints

// overload some constraints
k3.json(other_serialized);

var serialized = k3.json();

the resulting thing should be JSON-LD interpretable.