lib/plugins/config/config.js/Config/tabtabCompletionUninstall
class Config:  tabtabCompletionUninstall() {
    return BbPromise.try(() => {
      const { uninstall } = require('tabtab/lib/installer');
      return muteConsoleLog(() =>
        tabtabOptions.reduce(
          (previousOperation, options) => previousOperation.then(() => uninstall(options)),
          BbPromise.resolve()
        )
      ).then(() =>
        this.serverless.cli.log('Tab autocompletion uninstalled (for all configured shells).')
      );
    });
  }