angular-ui/ui-select — pull request #320 by amcdnl (2014-10-16 21:36:01+00:00)
Title: Adding ability to have a callback for highlighting an item

Adding ability to have callback when highlighting an item for cases like showing description beside the dropdown or something. select2 has this event called `select2-highlight`

| event name | description | example |
|---|---|---|
| `on-highlight` | Occurs when an item was hovered on | `on-highlight="showPreview($item)"` |