[css3-text] Editorial: Example 24 should be a note

Hi,

Example 24 (the one that says "One example of good fonts for emphasis  
marks [...]") isn't really an example, as it doesn't illustrate how to use  
features introduced by the specification.

Despite containing the word example early on in the sentence, I believe it  
really is a note, and should be relabeled as such.

  - Florian