Make ZoneID column name configurable

[dhixsingh]

The ZoneID column name is hardcoded and should instead be a configurable string.

ees/ees/src/main/java/io/github/agentsoz/ees/MessagingModel.java

Lines 161 to 169 in db5de76

	for (JSONObject feature : (Iterable<JSONObject>) features) {
	JSONObject properties = (JSONObject) feature.get("properties");
	String zoneId = (properties.get("SA1_MAIN11") != null) ?
	(String) properties.get("SA1_MAIN11") :
	(String) properties.get("SA1_MAIN16");
	if (zoneId == null) {
	logger.warn("Feature has no property named SA1_MAIN11 or SA1_MAIN16; discarding");
	continue;
	}

[dhixsingh]

Available since 2c6725c.