[conformal/btcd] 9ded3f: Generate usage from handler data in btcctl.

[Dave Collins]

  Branch: refs/heads/master
  Home:   https://github.com/conformal/btcd
  Commit: 9ded3fa2cfe27bddeedf7bb2ee5e42d91a3a829e
      
https://github.com/conformal/btcd/commit/9ded3fa2cfe27bddeedf7bb2ee5e42d91a3a829e
  Author: Dave Collins <da...@conformal.com>
  Date:   2013-10-22 (Tue, 22 Oct 2013)

  Changed paths:
    M util/btcctl/btcctl.go

  Log Message:
  -----------
  Generate usage from handler data in btcctl.

Rather than having to keep the usage in sync with the supported commands,
simply include the usage as a field in the command handlers map and
dynamically generate the usage from there.