Added expvars
One can launch expvarmon to monitor connections/memory usage:
expvarmon -ports="9050" -i=200ms -vars="mem:memstats.Alloc,mem:memstats.Sys,mem:memstats.HeapAlloc,mem:memstats.HeapInuse,,memstats.NumGC,duration:memstats.PauseTotalNs,Goroutines,Clients,RPS,Version"Test coverage improved thought slight refactoring