remove unused import

src/main/java/com/owncloud/android/ui/fragment/FileDetailActivitiesFragment.java

@@ -51,7 +51,6 @@ import com.owncloud.android.lib.common.OwnCloudClientManagerFactory;
 import com.owncloud.android.lib.common.operations.RemoteOperationResult;
 import com.owncloud.android.lib.common.utils.Log_OC;
 import com.owncloud.android.lib.resources.activities.GetRemoteActivitiesOperation;
-import com.owncloud.android.lib.resources.activities.models.Activity;
 import com.owncloud.android.lib.resources.activities.models.RichObject;
 import com.owncloud.android.ui.activity.FileActivity;
 import com.owncloud.android.ui.adapter.ActivityListAdapter;