code: public static Map<String, String> readPhoneTrunkAndExitCodes(final Locale plocale) {
      final PhoneCountryTrunkAndExitCodesConstants phoneTrunkAndExitCodes =
          GWT.create(PhoneCountryTrunkAndExitCodesConstants.class);
      return phoneTrunkAndExitCodes.phoneTrunkAndExitCodes();
    }
docs: read phone trunk an exit code map from property file.
  
  @return map of country code and combined string of trunk an exit code