Additions and enhancements (#14)

- add interactive API repl
- enhance cluster status output (use -v)
- add more ccr commands
- refactoring

cmd/root.go

@@ -79,6 +79,7 @@ func Main() int {
 			Ccr(conf),
 			Node(conf),
 			Doc(conf),
+			Repl(conf),
 		},
 
 		Before: func(ctx context.Context, cmd *cli.Command) (context.Context, error) {