OwnerPicker to support output options

Feature Suggestion

When selecting the User using the OwnerPicker that was recently contributed by @tragiclifestories, the output is User: john.smith

There is no option to just output john.smith for the user and no way to add other fields that you would like to be shown in the dropdown.

Possible Implementation

Introduce two new UI Options called allowedOutput to exclude the User: by defining the field name you would like to output and allowedMetadata to include specific fields you would like shown in the dropdown such as displayName.

        owner:
          title: Component Owner
          type: string
          description: Owner of the component 
          ui:field: OwnerPicker
          ui:options:
            allowedKinds: 
              - User
            allowedMetadata:
              - name
              - displayName 
            allowedOutput:
              - name

[freben]

Yeah, you can definitely make a separate picker implementation for this.

[OrkoHunter]

Thanks @regicsolutions !