[tex-live] README on CTAN

[Karl Berry]

All of these proposals make more work for me.  When it's important, I
don't mind, but this case is not important.  It's just one tiny file
with generic information that hardly anyone looks at.  So I don't want
to maintain it in multiple formats or generate different formats.  I
just want to edit one simple file and be done with it.

So I converted it (by hand :) to Markdown.  We'll see what it looks like
when it hits CTAN.  -k