add ExpandableDataPicker control
add ExpandableDataPicker samples
use ExpandablePicker's defaultKind as default kind for Repeater
Merge pull request #1560 from enyojs/BHV-9597-ryanjduffy

Fixes BHV-9597 - Expandable Picker needs to handle dynamic data

Looks good!

Reviewed-by: Aaron Tam (aaron.tam@lge.com)