tlv: rewrite syntax specifications using IETF ABNF

refs #4853

Change-Id: Iad79a63675279d53de2f7bb4891d10bf01d0424f
diff --git a/changelog.rst b/changelog.rst
index ddc616c..b24c849 100644
--- a/changelog.rst
+++ b/changelog.rst
@@ -4,6 +4,8 @@
 Version 0.3
 -----------
 
+- Rewrite TLV syntax specifications using `IETF Augmented BNF (RFC 5234) <https://tools.ietf.org/html/rfc5234>`__
+
 - **Interest**
 
   + Remove ``Selectors`` element