style(alerting): remove unused code

pkg/services/alerting/datasources/backends.go

-package datasources
-
-// GetSeries returns timeseries data from the datasource

pkg/services/alerting/datasources/graphite.go

-package datasources
-
-// import (
-// 	"bytes"
-// 	"encoding/json"
-// 	"fmt"
-// 	"io/ioutil"
-// 	"net/http"
-// 	"net/url"
-// 	"strconv"
-// 	"time"
-//
-// 	"github.com/grafana/grafana/pkg/components/simplejson"
-// 	"github.com/grafana/grafana/pkg/log"
-// 	m "github.com/grafana/grafana/pkg/models"
-// 	"github.com/grafana/grafana/pkg/util"
-// )
-//
-// type GraphiteClient struct{}
-//
-// type GraphiteSerie struct {
-// 	Datapoints [][2]float64
-// 	Target     string
-// }
-//
-// var DefaultClient = &http.Client{
-// 	Timeout: time.Minute,
-// }
-//
-// type GraphiteResponse []GraphiteSerie
-//
-// func (client GraphiteClient) GetSeries(rule m.AlertJob, datasource m.DataSource) (m.TimeSeriesSlice, error) {
-// 	v := url.Values{
-// 		"format": []string{"json"},
-// 		"target": []string{getTargetFromRule(rule.Rule)},
-// 		"until":  []string{"now"},
-// 		"from":   []string{"-" + strconv.Itoa(rule.Rule.QueryRange) + "s"},
-// 	}
-//
-// 	log.Trace("Graphite: sending request with querystring: ", v.Encode())
-//
-// 	req, err := http.NewRequest("POST", datasource.Url+"/render", nil)
-//
-// 	if err != nil {
-// 		return nil, fmt.Errorf("Could not create request")
-// 	}
-//
-// 	req.Body = ioutil.NopCloser(bytes.NewReader([]byte(v.Encode())))
-//
-// 	if datasource.BasicAuth {
-// 		req.Header.Add("Authorization", util.GetBasicAuthHeader(datasource.User, datasource.Password))
-// 	}
-//
-// 	res, err := DefaultClient.Do(req)
-//
-// 	if err != nil {
-// 		return nil, err
-// 	}
-//
-// 	if res.StatusCode != http.StatusOK {
-// 		return nil, fmt.Errorf("expected httpstatus 200, found %d", res.StatusCode)
-// 	}
-//
-// 	response := GraphiteResponse{}
-//
-// 	json.NewDecoder(res.Body).Decode(&response)
-//
-// 	var timeSeries []*m.TimeSeries
-// 	for _, v := range response {
-// 		timeSeries = append(timeSeries, m.NewTimeSeries(v.Target, v.Datapoints))
-// 	}
-//
-// 	return timeSeries, nil
-// }
-//
-// func getTargetFromRule(rule m.AlertRule) string {
-// 	json, _ := simplejson.NewJson([]byte(rule.Query))
-//
-// 	return json.Get("target").MustString()
-// }