Added clear functionality to cache

src/de/tud/kom/p2psim/impl/vehicular/caching/DefaultCachingComponent.java

@@ -108,4 +108,9 @@ public class DefaultCachingComponent implements CachingComponent, ConnectivityLi
 
 	}
 
+	@Override
+	public void clear() {
+		_cache.clear();
+	}
+
 }