message: Calculated tint colors from props
  If barTintColor is a function then pass true (standard height bar) to get the value
diff: @@ -7,9 +7,11 @@ declare module 'react-native' {
  }
  }
  -const NavigationBar = ({navigationImage, onNavigationPress, navigationHref, tintColor, title, titleFontSize = 20}) => {
  +const NavigationBar = ({navigationImage, onNavigationPress, navigationHref, barTintColor, tintColor, title, titleFontSize = 20}) => {
  + var barTintColor = (typeof barTintColor === 'function' ? barTintColor(true) : barTintColor) || '#fff';
  + var tintColor = (typeof tintColor === 'function' ? tintColor(true) : tintColor) || '#000';
  return (
  - <View style={{height: 56, flexDirection: 'row', alignItems: 'center', paddingStart: 16}}>
  + <View style={{height: 56, flexDirection: 'row', alignItems: 'center', paddingStart: 16, backgroundColor: barTintColor}}>
  {navigationImage && (
  <View href={navigationHref} style={{width: 56}}>
  <TouchableOpacity onPress={onNavigationPress}>
  