Fix: FundingTrade is parsed incorrectly bitfinexcom#556

Author: derektu

lib/transports/ws2.js

@@ -979,7 +979,8 @@ class WSv2 extends EventEmitter {
     let data = payload
 
     if (this._transform) { // correctly parse single trade/array of trades
-      const M = eventName[0] === 'f' ? FundingTrade : PublicTrade
+      /* const M = eventName[0] === 'f' ? FundingTrade : PublicTrade */
+      const M = eventName[0] === 'f' && data[0].length === 8 ? FundingTrade : PublicTrade      
       const trades = M.unserialize(data)
 
       if (_isArray(trades) && trades.length === 1) {