- Added "view" parameters (paramnb.view.HTML and paramnb.view.Image) to link widgets to an output/display region.
- Added widgets for Date, Range and Color parameters
- Dict, Tuple, and List parameters can now be edited (with the results evaluated using `ast.literal_eval`)
- Widgets display evaluation and validation errors as yellow and red borders respectively
- Added `continuous_update` parameter to control whether callbacks are executed as sliders are dragged.
Backwards compatibility:
- The callback is now supplied the latest changed parameters and values as keywords
- Button callback now passes the parameterized instance/class to the callback
- `continuous_update` is False by default to avoid queuing up multiple callbacks during slider drags, in case the callbacks take time to run. You can restore the old behavior by setting `continuous_update=True`.