Stanislav 078c404c3b Prometheus endpoint ()
* Add prometheus collector and route

* dep ensure -add github.com/prometheus/client_golang/prometheus

* dep ensure -update github.com/golang/protobuf

* add metrics to reserved usernames

* add comment head in metrics package

* fix style imports

* add metrics settings

* add bearer token check

* mapping metrics configs

* fix lint

* update config cheat sheet

* update conf sample, typo fix
..
internal/util Prometheus endpoint ()
nfs Prometheus endpoint ()
xfs Prometheus endpoint ()
LICENSE Prometheus endpoint ()
NOTICE Prometheus endpoint ()
buddyinfo.go Prometheus endpoint ()
doc.go Prometheus endpoint ()
fs.go Prometheus endpoint ()
ipvs.go Prometheus endpoint ()
mdstat.go Prometheus endpoint ()
mountstats.go Prometheus endpoint ()
net_dev.go Prometheus endpoint ()
proc.go Prometheus endpoint ()
proc_io.go Prometheus endpoint ()
proc_limits.go Prometheus endpoint ()
proc_ns.go Prometheus endpoint ()
proc_stat.go Prometheus endpoint ()
stat.go Prometheus endpoint ()
xfrm.go Prometheus endpoint ()