Feature request: More color customization

[iankberry]

This library provides many options to customize the picker colors, but there are a few areas that are inconsistent/missing between the platforms.

On iOS the containerColor (background) and most of the contentColor (text) style properties appear to have no effect.

On Android there doesn't appear to be any way to customize the yearmonth colors and it doesn't respect the color scheme like iOS, so the text is unreadable in dark mode. Ideally it would follow the colors from the styles prop though as we have our own text/accent colors.

Thanks for your consideration!

Style object:

const datePickerColors = useMemo((): Styles => ({
        accentColor: theme.color.green,
        containerColor: theme.background.primary,
        currentYearContentColor: theme.color.green,
        dayContentColor: theme.text.primary,
        dayInSelectionRangeContentColor: theme.text.tertiary,
        navigationContentColor: theme.text.primary,
        periodSelectorSelectedContainerColor: theme.color.green,
        selectedDayContainerColor: theme.color.green,
        selectedDayContentColor: theme.colorScheme === 'light' ? theme.color.white : theme.color.black,
        selectedYearContainerColor: theme.color.green,
        selectedYearContentColor: theme.colorScheme === 'light' ? theme.color.white : theme.color.black,
        subheadContentColor: theme.text.primary,
        titleContentColor: theme.text.primary,
        todayContentColor: theme.color.green,
        todayDateBorderColor: theme.color.green,
        weekdayContentColor: theme.text.tertiary,
        yearContentColor: theme.text.secondary,
    }), [ theme.colorScheme ]);

Screenshots showing the differences between the two platforms in dark mode: