Log payloads as hex string

[mauvm]

It now logs the payloads buffer as object:

{"name":"concava-connector-spul","hostname":"6888f2040398","pid":17,"level":30,"type":"data","timestamp":1464032114,"addr":"::ffff:188.65.190.625303","deviceId":"53ada80f405c59ae","blocks":5,"size":38,"payloads":{"type":"Buffer","data":[209,88,67,87,73,89,67,87,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,242,0,188,39,0,0,204,1,81,15,184,0,73,89,67,87,193,89,67,87,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,243,0,189,39,0,0,204,1,81,15,184,0,193,89,67,87,57,90,67,87,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,243,0,189,39,0,0,204,1,83,15,183,0,57,90,67,87,177,90,67,87,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,243,0,189,39,0,0,204,1,86,15,184,0,177,90,67,87,41,91,67,87,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,255,127,244,0,189,39,0,0,199,1,81,15,183,0]},"msg":"","time":"2016-05-23T19:35:14.110Z","v":0}