added note

README.md

@@ -22,9 +22,10 @@ libchat6 is a complete library that handles an IPv6 only, peer-to-peer, end-to-e
 * ... ?
 
 ## notes
-* replace RSA by Ed25519
 * use TAI64 for timestamps
 
+## NEW PROTOCOL TO BE DOCUMENTED!!!
+
 ## Protocol
 
 ```
@@ -37,7 +38,7 @@ The timestamp is a unixtimestamp represented as a 64 bits signed integer.
 
 ### PROOF
 
-The PROOF token proves the origin and signs the message. It is composed of the hash of the client concatenated with a SHA256 of the message without the PROOF and with a metric value of 0.
+The PROOF token proves the origin and signs the message. It is composed of the hash of the client concatenated with a hash of the message without the PROOF and with a metric value of 0 (if present).
 
 ### Key=value pairs