class Thor

def register(klass, subcommand_name, usage, description, options = {})

description:: Description for the subcommand
usage:: Short usage for the subcommand
command:: Subcommand name to use
klass:: Thor subclass to register
==== Parameters

Registers another Thor subclass as a command. 
def register(klass, subcommand_name, usage, description, options = {})
  if klass <= Thor::Group
    desc usage, description, options
    define_method(subcommand_name) { |*args| invoke(klass, args) }
  else
    desc usage, description, options
    subcommand subcommand_name, klass
  end
end