A form control for selecting facet values.
Example
The selectedValuesChange event will emit an array of FacetValue objects.
(value: FacetValueFragment[]) => any[]Observable<FacetValueFragment[]>(val: any) => void() => voidArray<string | FacetValueFragment>() => void() => (selected: FacetValueFragment[]) => (fn: any) => (fn: any) => (isDisabled: boolean) => void() => (obj: string | FacetValueFragment[] | Array<string | number> | null) => void