Remove left over bits from the old heartbeat implementation.

lib/units/websocket/index.js

@@ -139,7 +139,6 @@ module.exports = function(options) {
             serial: message.serial
           , present: false
           , ready: false
-          , lastHeartbeatAt: null
           , using: false
           , likelyLeaveReason: 'device_absent'
           }

lib/wire/util.js

@@ -4,7 +4,6 @@ var wire = require('./')
 
 var wireutil = {
   global: '*ALL'
-, heartbeat: '*HB'
 , makePrivateChannel: function() {
     return uuid.v4(null, new Buffer(16)).toString('base64')
   }