code: function getClient(credentials) {
  	return new Promise((resolve, reject) => {
  		const ftp = new Ftp(credentials);
  		ftp.once('connect', () => {
  			resolve(ftp);
  		});
  	});
  }
docs: Initialize a new FTP client
  @param {Credentials} credentials - Access info for the FTP server
  @return {Promise<Ftp>} a promise for a FTP client