Lightweight inline formatting for NSAttributedString

For Cocoa developers: I’ve just put a small category on NSMutableAttributedString on Github. It applies *bold*, /italic/, _underline_, -strikethrough-, ^superscript^ and ~subscript~ styles, and handles */nested/* and *overlapping /styles* properly/. More details at https://github.com/jawj/NSMutableAttributedString-InlineStyles