@Override
	public void cleanup() {
		server.stop();
		try {
			FileUtils.deleteDirectory(remoteServerDirectory);
		}
		catch (IOException e) {
			throw new AssertionError("Deletion of directory should have worked", e);
		}
	}
A fixture that helps testing the ftp sink. instantiates and runs a local FTP server and exposes a {@link File} directory in order to be able
to check if the file pushed through FTP is present on the server side and if it has the same content as the file sent.

@author Franck Marchand
spring-xd-test-fixtures/src/main/java/org/springframework/xd/test/fixtures/FtpSink.java