custom label for each properties

Hello and thanks a lot for this very helpful plugin!

I was wondering if there was a way to customize the way the error message is sent by using a label instead of the property name.

For example, by using this kind of syntax:
```
schema: {
query: {
type: 'object',
required: ['score'],
properties: {
score: {
type: 'integer',
label: 'スコア',
errorMessage: {
type: '${/score}が数字ではない'
}
}
}
}
```
I would get the following
**スコア** "true"が数字ではない
instead of
**query/score** "true"が数字ではない

I am sorry if it is already written somewhere. I have read so many articles today that my head might explodes by the end of the day.