Remove "cfg" from node JSON configuations

Change the JSON node definition format from this:

{

type: "rotate",
id: "foo", 
cfg : { 
    angle: 45, 
    y: 1.0 
}

}

removing the intermediate "cfg", to this:
{

type: "rotate",
id: "foo", 
angle: 45, 
y: 1.0

}

The rationale being that all those properties are actually on the same namespace anyway, no benefit in that cfg.