Remove spring-boot-starter-validation from LoadBalancer dependencies. Fixes gh-992.

spring-cloud-loadbalancer/pom.xml

@@ -22,10 +22,6 @@
 			<groupId>org.springframework.cloud</groupId>
 			<artifactId>spring-cloud-context</artifactId>
 		</dependency>
-		<dependency>
-			<groupId>org.springframework.boot</groupId>
-			<artifactId>spring-boot-starter-validation</artifactId>
-		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-actuator</artifactId>

spring-cloud-loadbalancer/src/main/java/org/springframework/cloud/loadbalancer/cache/DefaultLoadBalancerCache.java

@@ -19,8 +19,6 @@ package org.springframework.cloud.loadbalancer.cache;
 import java.util.concurrent.Callable;
 import java.util.concurrent.ConcurrentMap;
 
-import javax.validation.constraints.Null;
-
 import com.stoyanr.evictor.ConcurrentMapWithTimedEviction;
 import com.stoyanr.evictor.map.ConcurrentHashMapWithTimedEviction;
 import com.stoyanr.evictor.scheduler.DelayedTaskEvictionScheduler;
@@ -93,7 +91,6 @@ public class DefaultLoadBalancerCache extends AbstractValueAdaptingCache {
 	}
 
 	@Override
-	@Null
 	protected Object lookup(Object key) {
 		return cache.get(key);
 	}