[#7] Add local tool for building database file

Added frostfs-locode-db CLI utility that can generate and view UN/LOCODE
database files. Go package
git.frostfs.info/TrueCloudLab/frostfs-node/pkg/util/locode copied to
this repository to eliminate interdependency between frostfs-node and
frostfs-locode-db projects. The process of building database files
reduced to starting make command.

Signed-off-by: George Bartolomey <george@bh4.ru>

locode_info.go

@@ -0,0 +1,55 @@
+package main
+
+import (
+	locodedb "git.frostfs.info/TrueCloudLab/frostfs-locode-db/pkg/locode/db"
+	locodebolt "git.frostfs.info/TrueCloudLab/frostfs-locode-db/pkg/locode/db/boltdb"
+	"github.com/spf13/cobra"
+)
+
+const (
+	locodeInfoDBFlag   = "db"
+	locodeInfoCodeFlag = "locode"
+)
+
+var (
+	locodeInfoDBPath string
+	locodeInfoCode   string
+
+	locodeInfoCmd = &cobra.Command{
+		Use:   "info",
+		Short: "Print information about UN/LOCODE from FrostFS database",
+		Run: func(cmd *cobra.Command, _ []string) {
+			targetDB := locodebolt.New(locodebolt.Prm{
+				Path: locodeInfoDBPath,
+			}, locodebolt.ReadOnly())
+
+			err := targetDB.Open()
+			ExitOnErr(cmd, "", err)
+
+			defer targetDB.Close()
+
+			record, err := locodedb.LocodeRecord(targetDB, locodeInfoCode)
+			ExitOnErr(cmd, "", err)
+
+			cmd.Printf("Country: %s\n", record.CountryName())
+			cmd.Printf("Location: %s\n", record.LocationName())
+			cmd.Printf("Continent: %s\n", record.Continent())
+			if subDivCode := record.SubDivCode(); subDivCode != "" {
+				cmd.Printf("Subdivision: [%s] %s\n", subDivCode, record.SubDivName())
+			}
+
+			geoPoint := record.GeoPoint()
+			cmd.Printf("Coordinates: %0.2f, %0.2f\n", geoPoint.Latitude(), geoPoint.Longitude())
+		},
+	}
+)
+
+func initUtilLocodeInfoCmd() {
+	flags := locodeInfoCmd.Flags()
+
+	flags.StringVar(&locodeInfoDBPath, locodeInfoDBFlag, "", "Path to FrostFS UN/LOCODE database")
+	_ = locodeInfoCmd.MarkFlagRequired(locodeInfoDBFlag)
+
+	flags.StringVar(&locodeInfoCode, locodeInfoCodeFlag, "", "UN/LOCODE")
+	_ = locodeInfoCmd.MarkFlagRequired(locodeInfoCodeFlag)
+}