Examples database

[Klortho]

These are some ideas for requirements for a database of examples.

• Mulberry's tag libraries have an elaborate scheme for using full, valid XML files as examples, and then eliding them for display on individual pages. Maybe we could re-use that?
• OTOH, it would be nice if the examples could remain unsullied (their scheme adds a bunch of PIs, which would be hard to maintain).
• We need a method to render:
  • Relevant portions of the document, with ellipses for elided parts
  • Pretty-printed, syntax highlighted
  • Also highlight the relevant keyword or section
  • The recommendations document should specify how the example is to be rendered, in a data-driven way