code: function echo(command) {
          return command.getUser()
              .then((user) => {
                  const content = (command.parent.text || '').split('\n').map((line) => `> ${line}`);
                  content.unshift(`@${user.username} said:`);
                  command.reply(content.join('\n'));
              });
      }
docs: Echo the command contents back to the user
  
  @param {Command} command The command that contains the `!echo` command
  @returns {Promise} Resolves when processing is complete