pkg/util/{ip.go,url.go}: Fix some golint issues

See,
$ gometalinter --vendor --deadline 10m --disable-all --enable=golint  ./...
ip.go:8:6⚠️ func SplitIpPort should be SplitIPPort (golint)
url.go:14:6⚠️ func NewUrlQueryReader should be NewURLQueryReader (golint)
url.go:9:6⚠️ type UrlQueryReader should be URLQueryReader (golint)
url.go:37:6⚠️ func JoinUrlFragments should be JoinURLFragments (golint)

pkg/services/sqlstore/sqlstore.go

@@ -223,7 +223,7 @@ func (ss *SqlStore) buildConnectionString() (string, error) {
 			cnnstr += "&tls=custom"
 		}
 	case migrator.POSTGRES:
-		host, port, err := util.SplitIpPort(ss.dbCfg.Host, "5432")
+		host, port, err := util.SplitIPPort(ss.dbCfg.Host, "5432")
 		if err != nil {
 			return "", err
 		}