def tcfg_get(key)
      t_tcfg = tcfg
      unless t_tcfg.key? key
        raise NoSuchConfigurationKeyError, "No configuration defined for '#{key}'"
      end
      t_tcfg[key]
    end
def tcfg_get(key)
      t_tcfg = tcfg
      unless t_tcfg.key? key
        raise NoSuchConfigurationKeyError, "No configuration defined for '#{key}'"
      end
      t_tcfg[key]
    end
return a single piece of configuration by key

 @param key [String] the configuration to return
 @return [String, Integer, FixNum, Array, Hash] the value of the configuration from the resolved configuration