Add bookkeeper ledger commands

[zymap]

---

Motivation

Introduce a admin client for bookKeeper.
Add ledger commands to the admin client

Modifications

• adjust the admin to provide the bookKeeper service
• Add ledger commands

Ouput:

➜  pulsarctl git:(bookie-command) ./pulsarctl bookies ledger delete -h
USED FOR:
    This command is used for deleting a ledger.

REQUIRED PERMISSION:
    none

OUTPUT:
    #normal output
    Successfully delete the ledger (ledger-id)

Usage: pulsarctl bookies ledger delete [flags]

Examples:
    #Delete the specified ledger
    pulsarctl bookies ledger delete --ledger-id (ledger-id)



Ledger flags:
      --ledger-id int   the delete ledger id (default -1)

Common flags:
  -s, --admin-service-url string    The admin web service url that pulsarctl connects to. (default "http://localhost:8080")
      --auth-params string          Authentication parameters are used to configure the public and private key files required by tls
                                     For example: "tlsCertFile:val1,tlsKeyFile:val2"
      --bookie-service-url string   The bookie web service url that pulsarctl connects to. (default "http://localhost:8081")
  -C, --color string                toggle colorized logs (true,false,fabulous) (default "true")
  -h, --help                        help for this command
      --tls-allow-insecure          Allow TLS insecure connection
      --tls-trust-cert-pat string   Allow TLS trust cert file path
  -v, --verbose int                 set log level, use 0 to silence, 4 for debugging (default 3)

Use 'pulsarctl bookies ledger delete [command] --help' for more information about a command.

[zymap]

@sijie I add the bookie client into the pulsarctl. Can you take a quick look to see if I'm on the right track? Thanks!

[zymap]

@sijie PTAL