Better use of srfi-35 conditions.

This commit defines `&not-found` and `&forbidden` condition types and allows
special handlers to be registered to handle them during requests.

All default handlers now ignore the value assigned to the `%default-headers`
parameter and always use "text/plain; charset=utf-8" as content type.

`cantius.scm` now imports SRFI-35 is using prefix, copyright years have been
updated.

0 files changed, 0 insertions, 0 deletions