Add missing @since tag to IntComparator

Change-Id: Ic190ab404ccb3af675cdd90cac231ce6e856ea68
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/IntList.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/IntList.java
index cc4f0a4..635dd6a 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/IntList.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/IntList.java
@@ -220,6 +220,8 @@ public String toString() {
 
 	/**
 	 * A comparator of primitive ints.
+	 *
+	 * @since 6.6
 	 */
 	public interface IntComparator {