I cannot write accents and Drupal clean white spaces

Have you tried dev versions? there is a fix there for the encoding problems.

Being a plain textfile, I don't see how you plan to insert there an image

An image? ASCII art rules! Or should we call it Unicode art? Anyhow, I guess that's what he means by painting a logo and that the whitespace got cleanup up, messing with his creativity.

Same problem here.

To get it working, I made a little change in the humanstxt.module file, line 53. The idea is to specify the content type's charset. As you can see, I just added 'charset=utf-8' right after 'text/plain;' :

/**
 * Callback to display humans.txt file.
 */
function humanstxt_file() {
	$content = array();
 	$content[] = _humanstxt_get_content();

	// Trim any extra whitespace and filter out empty strings.
	$content = array_map('trim', $content);
	$content = array_filter($content);
  
	drupal_add_http_header('Content-type', 'text/plain; charset=utf-8');
	echo implode("\n", $content);
	exit;
}

I'm happy to include this, would you submit a patch?

Removed a couple of lines that trimmed the spaces so ascii artists are happy.