Add support for number format expression

[tobrun]

This issue tracks adding number-format expression to the android binding. Core PR is happening in #14840, original core issue in #13632 (which is a gl-js parity issue to mapbox/mapbox-gl-js#7626).

[1ec5]

Besides adding number-format to the Android expression DSL, the actual formatting should be implemented in Java in platform/android/src/string_util.cpp and platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/utils/StringUtils.java based on NumberFormat.format(double).

/ref #14840 (review)

[tobrun]

Started to work on this, have a basic version working.The following expression will result in a symbol layer as shown in screenshot:

numberFormatSymbolLayer.setProperties(
  textField(
    numberFormat(123.456789, locale("nl"), currency("EUR"))
  )
);

To be investigated why the € sign isn't showing properly though.

[tobrun]

Capturing from @jmalanen that the correct locale for this configuration = nl-NL

    numberFormatSymbolLayer.setProperties(
      textField(
        numberFormat(123.456789, locale("nl-NL"), currency("EUR"))
      )
    );

[tobrun]

landed in #15424