[ANN] Markdown 1.0b5 (private beta)

[John Gruber]

OK, gang, I've put together a 1.0b5 beta of Markdown:

<http://daringfireball.net/projects/downloads/Markdown_1.0b5.zip>

This is a semi-private beta release, which I'm only announcing here
on the list. It's not a secret (this list has public archives, for
example), but I'd prefer it if it were only used by the small group
of people subscribed here.

I'd like to move quickly towards 1.0 final, with a couple of
incremental betas. But I don't want the public at-large to be
exposed to a bunch of betas, some of which might have ugly bugs.
1.0b4 seems to be stable and useful, so we'll let the masses stick
with that one for a bit longer.

Here are my change notes for this release:

1.0b5: 

*   If Markdown() is called without a string parameter, it now
    returns an empty string. Previously, it'd generate warnings.
    This should never happen, but there's no harm in safeguarding
    against it.

*   Workaround for supporting <ins> and <del> as block-level tags.
    This only works if the start and end tags are on lines by
    themselves.

*   Three or more underscores can now be used for horizontal rules.

*   Lines containing only whitespace are trimmed from blockquotes.

*   You can now optionally wrap URLs with angle brackets -- like so:
    `<http://example.com>` -- in link definitions and inline links and
    images.

*   `_` and `*` characters in links and images are no longer escaped
    as HTML entities. Instead, we use the ridiculous but effective MD5
    hashing trick that's used to hide these characters elsewhere. The
    end result is that the HTML output uses the literal `*` and `_`
    characters, rather than the ugly entities.

-J.G.