cli: Add empty neofs-cli app structure

In the following release `neofs-cli` will be used to directly manage NeoFS Node.
All required definitions and interfaces are also moving from `neofs-api` to
`neofs-node` repository, so it's more convinient to have `neofs-cli` here.

Signed-off-by: Stanislav Bogatyrev <stanislav@nspcc.ru>

cmd/neofs-cli/modules/netmap.go

@@ -0,0 +1,31 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+// netmapCmd represents the netmap command
+var netmapCmd = &cobra.Command{
+	Use:   "netmap",
+	Short: "Operations with Network Map",
+	Long:  `Operations with Network Map`,
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Println("netmap called")
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(netmapCmd)
+
+	// Here you will define your flags and configuration settings.
+
+	// Cobra supports Persistent Flags which will work for this command
+	// and all subcommands, e.g.:
+	// netmapCmd.PersistentFlags().String("foo", "", "A help for foo")
+
+	// Cobra supports local flags which will only run when this command
+	// is called directly, e.g.:
+	// netmapCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
+}