Support multiple values (Listbox)

[DavidVollmers]

• Add Values property and ValuesChanged event handler to supply an array of values to the Listbox component, which then allows selecting/toggling multiple options

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (6768fa4) 41.65% compared to head (06afb66) 42.36%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #44 +/- ## ========================================== + Coverage 41.65% 42.36% +0.70% ========================================== Files 82 82 Lines 2290 2299 +9 Branches 441 445 +4 ========================================== + Hits 954 974 +20 + Misses 1200 1189 -11 Partials 136 136 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.