Set the spring.cloud.task.closecontext_enable default to false

resolves #364

spring-cloud-task-core/src/main/java/org/springframework/cloud/task/configuration/TaskProperties.java

@@ -60,7 +60,7 @@ public class TaskProperties {
 	 * When set to true the context is closed at the end of the task.  Else
 	 * the context remains open.
 	 */
-	private Boolean closecontextEnabled = true;
+	private Boolean closecontextEnabled = false;
 
 	public String getExternalExecutionId() {
 		return externalExecutionId;