* implement `backspace` behaviour in tests
* add `Delete` Key
* implement `nullable` mode on Combobox in single value mode
If you pass a `nullable` prop to the Combobox, then it's possible to
unset the Combobox value by setting it to `null`.
This is triggered by removing all text from the input which will reset
the value itself as well.
* update changelog
Robin Malfait
ab6310c278