add configuration to disable listening on ipv6

controllers/nginx/pkg/config/config.go

@@ -97,6 +97,9 @@ type Configuration struct {
 	//http://nginx.org/en/docs/http/ngx_http_log_module.html
 	DisableAccessLog bool `json:"disable-access-log,omitempty"`
 
+	// DisableIpv6 disable listening on ipv6 address
+	DisableIpv6 bool `json:"disable-ipv6,omitempty"`
+
 	// EnableStickySessions enabled sticky sessions using cookies
 	// https://bitbucket.org/nginx-goodies/nginx-sticky-module-ng
 	// By default this is disabled
@@ -249,6 +252,7 @@ func NewDefault() Configuration {
 	cfg := Configuration{
 		ClientHeaderBufferSize:  "1k",
 		DisableAccessLog:        false,
+		DisableIpv6:		 false,
 		EnableDynamicTLSRecords: true,
 		ErrorLogLevel:           errorLevel,
 		HSTS:                    true,