r1512804 broke immutability

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@1659953 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/src/main/java/org/apache/commons/compress/archivers/ArchiveStreamFactory.java b/src/main/java/org/apache/commons/compress/archivers/ArchiveStreamFactory.java
index be422d3..6443e0a 100644
--- a/src/main/java/org/apache/commons/compress/archivers/ArchiveStreamFactory.java
+++ b/src/main/java/org/apache/commons/compress/archivers/ArchiveStreamFactory.java
@@ -72,7 +72,6 @@
  * in.close();
  * </pre>
  * 
- * @Immutable
  */
 public class ArchiveStreamFactory {