infranw: fixed model backward compatibility (#17)

* infranw: fixed model backward compatibility

* fix typo error

* Updated comments - default value for nwType

Author: pkeerthana

contivModel.go

@@ -1874,6 +1874,10 @@ func ValidateNetwork(obj *Network) error {
 		return errors.New("networkName string too long")
 	}
 
+	if obj.NwType == "" {
+		obj.NwType = "data"
+	}
+
 	nwTypeMatch := regexp.MustCompile("^(infra|data)$")
 	if nwTypeMatch.MatchString(obj.NwType) == false {
 		return errors.New("nwType string invalid format")

network.json

@@ -20,6 +20,7 @@
 				"nwType": {
 					"type": "string",
 					"format": "^(infra|data)$",
+					"default": "\"data\"",
 					"title": "Network Type",
 					"showSummary": true
 				},