- Update modeling of needham schroeder to better reflect the modelling in

SPORE:
    - pk is not known to all agents, only pk(Simon) is known
- Use new naming convention:
    - Protocol name starting with an @ means internal protocol
    - For non internal protocols naming is as follows:
      protocolname-variant^subprotocol
    For example: yahalom-Lowe^KeyCompromise meaning the key compromise sub
    protocol of the Lowe variant of the Yahalom protocol.

spdl/SPORE/yahalom.spdl

@@ -14,7 +14,7 @@ usertype SessionKey;
 const Fresh: Function;
 const Compromised: Function;
 
-protocol yahalomSessionKeyCompromise(C)
+protocol yahalom^KeyCompromise(C)
 {
     // Read the names of 3 agents and disclose a session between them including
     // corresponding session key to simulate key compromise