pull Lifecycle interface up to interface

engine/src/main/java/org/archive/crawler/framework/Frontier.java

@@ -35,6 +35,7 @@ import org.archive.modules.fetcher.FetchStats;
 import org.archive.net.UURI;
 import org.archive.util.MultiReporter;
 import org.json.JSONException;
+import org.springframework.context.Lifecycle;
 
 
 /**
@@ -105,7 +106,7 @@ import org.json.JSONException;
  * @see org.archive.crawler.framework.ToeThread
  * @see org.archive.crawler.settings.ModuleType
  */
-public interface Frontier extends MultiReporter {
+public interface Frontier extends Lifecycle, MultiReporter {
 
     /**
      * Get the next URI that should be processed. If no URI becomes availible

engine/src/main/java/org/archive/crawler/frontier/AbstractFrontier.java

@@ -91,7 +91,6 @@ import org.json.JSONException;
 import org.json.JSONObject;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.ApplicationEvent;
-import org.springframework.context.Lifecycle;
 
 /**
  * Shared facilities for Frontier implementations.
@@ -101,7 +100,6 @@ import org.springframework.context.Lifecycle;
 public abstract class AbstractFrontier 
     implements Frontier, 
                Serializable, 
-               Lifecycle, // InitializingBean, 
                SeedListener, 
                HasKeyedProperties,
                ExtractorParameters {