[BK-SUPPORT-PART-2] Support bookkeeper ledger commands

[zymap]

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Master Issue: #127

Motivation

Support bookkeeper ledger commands in Pulsarctl

Modifications

Add bookkeeper ledger commands

Output

➜  pulsarctl-yong git:(ledger_cmd) ./pulsarctl bookkeeper  ledger
Operations about ledger

Usage: pulsarctl bookkeeper ledger [flags]

Commands:
  delete      Delete a ledger
  get         Get the metadata of a ledger
  list        list all the ledgers
  read        Read a range of entries of a ledger

Aliases: ledger,

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:8080")
  -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
      --token string                Using the token to authentication
      --token-file string           Using the token file to authentication
  -v, --verbose int                 set log level, use 0 to silence, 4 for debugging (default 3)

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