Signature: add SignatureNonce and Timestamp

Change-Id: Ie906c44076ed2c29e0574c13fabed397d102a6ce
Refs: #4599
diff --git a/types.rst b/types.rst
index ea676ce..f4da6f9 100644
--- a/types.rst
+++ b/types.rst
@@ -65,6 +65,10 @@
 +---------------------------------------------+------------------+-----------------+
 | KeyDigest                                   | 29               | 0x1d            |
 +---------------------------------------------+------------------+-----------------+
+| SignatureNonce                              | 38 (non-critical)| 0x26            |
++---------------------------------------------+------------------+-----------------+
+| Timestamp                                   | 40 (non-critical)| 0x28            |
++---------------------------------------------+------------------+-----------------+
 |                     **Link Object**                                              |
 +---------------------------------------------+------------------+-----------------+
 | Delegation                                  | 31               | 0x1f            |
@@ -81,7 +85,8 @@
 | Number range   | Designation                                               |
 +================+===========================================================+
 | 0, 3, 4,       |                                                           |
-| 35, 37-79      | Reserved for future assignments (1-byte encoding)         |
+| 35, 37, 39,    |                                                           |
+| 41-79          | Reserved for future assignments (1-byte encoding)         |
 +----------------+-----------------------------------------------------------+
 | 9              | Reserved, formerly `Selectors`                            |
 +----------------+-----------------------------------------------------------+