Add @since tag to new DirCache#findEntry

Change-Id: Ia58efd178a4571c013bf1104d1da956a86fd7029
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCache.java

@@ -761,6 +761,7 @@ public class DirCache {
 	 * @return if >= 0 then the return value is the position of the entry in the
 	 *         index; pass to {@link #getEntry(int)} to obtain the entry
 	 *         information. If < 0 the entry does not exist in the index.
+	 * @since 3.4
 	 */
 	public int findEntry(final byte[] p, final int pLen) {
 		int low = 0;