Add Json Return Type to DynamicScripts

[osmanaslancan]

example LookupScript

{
    "items": [
        {
            "EmployeeID": 2,
            "FullName": "Andrew Fuller"
        },
        {
            "EmployeeID": 9,
            "FullName": "Anne Dodsworth"
        },
    ],
    "idField": "EmployeeID",
    "textField": "FullName"
}

example RemoteData

{
    "Username": "admin",
    "DisplayName": "admin",
    "IsAdmin": true,
    "Permissions": {
        "Administration:Security": true,
        "Administration:Translation": true,
    }
}

example RegisteredScripts

{
    "Lookup.Northwind.Shipper": "637949582408073162",
    "Columns.Northwind.Shipper": "637949582408073173",
}