Static Property

Can we have support to add static properties in the schema such that it's replicated into the data.

```
// schema.json
// code before this
"someKey": {
"type": "array",
"items": {
"someInnerKey": {
},
"someStaticKey": {
},
},
},
// code after this
```

And the resulting data would look like this, where the contents of `someStaticKey` is the same for all array elements of `someKey`.

```
// data before this
"someKey": [
{
"someInnerKey": {
// InnerKeyData1
},
"someStaticKey": {
// StaticData
},
},
{
"someInnerKey": {
// InnerKeyData2
},
"someStaticKey": {
// StaticData
},
},
],
// data after this
```