add more fields to execution trace

nextflow.config

@@ -341,6 +341,7 @@ report {
 trace {
     enabled = true
     file    = "${params.tracedir}/execution_trace_${trace_timestamp}.txt"
+    fields  = "task_id,hash,name,status,exit,duration,submit,duration,realtime,%cpu,%mem,peak_rss,peak_vmem,rchar,wchar"
 }
 dag {
     enabled = true