Implement minimal NUT client and use it instead of upsc

cmd/nut_exporter/main.go

@@ -3,13 +3,14 @@ package main
 import (
 	"net/http"
 
+	"honnef.co/go/nut"
+
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
-	"honnef.co/go/nut_exporter"
 )
 
 func main() {
-	c := nut_exporter.NewNUTCollector([]string{"main"}, nil)
+	c := nut.NewCollector([]string{"localhost"})
 	prometheus.MustRegister(c)
 	http.Handle("/metrics", promhttp.Handler())
 	http.ListenAndServe(":9999", nil)