feat: placeholder for v1 subcommands (#135)

* feat: placeholder for v1 subcommands

* chore: more usage comments

cmd/influx/main.go

@@ -50,6 +50,7 @@ var app = cli.App{
 		newDashboardsCommand(),
 		newExportCmd(),
 		newSecretCommand(),
+		newV1SubCommand(),
 	},
 }
 

cmd/influx/v1_commands.go

@@ -0,0 +1,14 @@
+package main
+
+import "github.com/urfave/cli/v2"
+
+func newV1SubCommand() *cli.Command {
+	return &cli.Command{
+		Name:  "v1",
+		Usage: "InfluxDB v1 management commands",
+		Subcommands: []*cli.Command{
+			newV1DBRPCmd(),
+			// etc
+		},
+	}
+}

cmd/influx/v1_dbrp.go

@@ -0,0 +1,19 @@
+package main
+
+import "github.com/urfave/cli/v2"
+
+func newV1DBRPCmd() *cli.Command {
+	return &cli.Command{
+		Name:        "dbrp",
+		Usage:       "Commands to manage database and retention policy mappings for v1 APIs",
+		Subcommands: []*cli.Command{
+			// newV1DBRPListCmd(),
+			// newV1DBRPCreateCmd(),
+			// newV1DBRPDeleteCmd(),
+			// newV1DBRPUpdateCmd(),
+		},
+	}
+}
+
+// commands will be implemented below, with business logic residing in their
+// respective client package, like "v1_dbrp"