Add missing @since tags for new API

Change-Id: I8db29a0313fbc476152cef47f2eaa76954f1e280
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit.lfs.server/src/org/eclipse/jgit/lfs/server/LfsObject.java

 /**
  * LFS object.
  *
+ * @since 4.5
  */
 public class LfsObject {
 	String oid;

org.eclipse.jgit.lfs.server/src/org/eclipse/jgit/lfs/server/LfsProtocolServlet.java

 	 * @return the large file repository storing large files or null if the
 	 *         request is not supported.
 	 * @throws LfsException
+	 * @since 4.5
 	 */
 	protected abstract LargeFileRepository getLargeFileRepository(
 			LfsRequest request, String path) throws LfsException;
 
-	/** LFS request. */
+	/**
+	 * LFS request.
+	 *
+	 * @since 4.5
+	 */
 	protected static class LfsRequest {
 		private String operation;
 

org.eclipse.jgit/src/org/eclipse/jgit/revwalk/DepthWalk.java

 			return REINTERESTING;
 		}
 
+		/**
+		 * @since 4.5
+		 */
 		@Override
 		public ObjectWalk toObjectWalkWithSameObjects() {
 			ObjectWalk ow = new ObjectWalk(reader, depth);