add lifecycle properties for making service registration optional

spring-cloud-consul-discovery/src/main/java/org/springframework/cloud/consul/discovery/ConsulDiscoveryClientConfiguration.java

@@ -55,6 +55,11 @@ public class ConsulDiscoveryClientConfiguration {
 		return new HeartbeatProperties();
 	}
 
+	@Bean
+	public LifecycleProperties lifecycleProperties() {
+		return new LifecycleProperties();
+	}
+
 	@Bean
 	public ConsulDiscoveryProperties consulDiscoveryProperties() {
 		return new ConsulDiscoveryProperties();

spring-cloud-consul-discovery/src/main/java/org/springframework/cloud/consul/discovery/ConsulLifecycle.java

@@ -45,6 +45,9 @@ public class ConsulLifecycle extends AbstractDiscoveryLifecycle {
 	@Autowired
 	private ConsulDiscoveryProperties properties;
 
+	@Autowired
+	private LifecycleProperties lifecycleProperties;
+
 	@Autowired(required = false)
 	private TtlScheduler ttlScheduler;
 
@@ -170,7 +173,7 @@ public class ConsulLifecycle extends AbstractDiscoveryLifecycle {
 
 	@Override
 	protected boolean isEnabled() {
-		return properties.isEnabled();
+		return lifecycleProperties.isEnabled();
 	}
 
 	/**

spring-cloud-consul-discovery/src/main/java/org/springframework/cloud/consul/discovery/LifecycleProperties.java

@@ -0,0 +1,14 @@
+package org.springframework.cloud.consul.discovery;
+
+import lombok.Data;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+/**
+ * @author Aleksandr Tarasov (aatarasoff)
+ */
+@ConfigurationProperties(prefix = "spring.cloud.consul.discovery.lifecycle")
+@Data
+public class LifecycleProperties {
+	private boolean enabled = true;
+}