Render out italics at all sizes.

[Lukasa]

Resolves #11.

[hbrls]

It looks good with my document. But that's semantically different from the original one.

The original regex (\\*)\\w[^*]+\\w(\\*) means:

*    word_char    not_*    word_char    *

While the pr (\\*)[^*]+(\\*) means:

*    not_*    *

[Lukasa]

To be clear, we need to be semantically different from the original regex, because the original regex requires a minimum of two word characters.