Minor: use "platform.*" as the naming hierarchy for protocols that are supposed to be standardised.

src/main/kotlin/contracts/protocols/TwoPartyTradeProtocol.kt

@@ -49,7 +49,7 @@ import java.time.Instant
  * To see an example of how to use this class, look at the unit tests.
  */
 object TwoPartyTradeProtocol {
-    val TRADE_TOPIC = "com.r3cev.protocols.trade"
+    val TRADE_TOPIC = "platform.trade"
 
     fun runSeller(smm: StateMachineManager, timestampingAuthority: LegallyIdentifiableNode,
                   otherSide: SingleMessageRecipient, assetToSell: StateAndRef<OwnableState>, price: Amount,

src/main/kotlin/core/node/TimestamperNodeService.kt

@@ -55,7 +55,7 @@ class TimestamperNodeService(private val net: MessagingService,
                              private val clock: Clock = Clock.systemDefaultZone(),
                              val tolerance: Duration = 30.seconds) {
     companion object {
-        val TIMESTAMPING_PROTOCOL_TOPIC = "dlg.timestamping.request"
+        val TIMESTAMPING_PROTOCOL_TOPIC = "platform.timestamping.request"
 
         private val logger = LoggerFactory.getLogger(TimestamperNodeService::class.java)
     }