feat(select): add on-confirm-remove property

[y4nnL]

Select

Attribute on-confirm-remove

When multiple is true, you may provide this handler before an item is removed from the selection. This handler is passed the item to remove and must return a promise. If the return value of that promise is truthy, the item is removed from the selection, otherwise it is kept.

<oui-select
    model="$ctrl.model"
    items="$ctrl.items"
    multiple="true"
    on-confirm-remove="$ctrl.onConfirmRemove(item)">
</oui-select>

async onConfirmRemove(item) {
  try {
    const removed = await doSomeAsyncTasksWith(item);
    return removed;
  } catch (e) {
    return false;
  }
}