Hi,

In order to make the blocks stand out more clearly in the mix of prose, code
and table results of many Babel Org files, I've added 2 new faces:

- org-block-begin-line
- org-block-end-line

These apply to the line just before and after the block's body:

#+srcname: top-10-dossiers-with-many-prestations
#+begin_src sql                                     <<< org-block-begin-line
SELECT TOP 10 prsPfiID_fk, COUNT(*) AS '# Prestations'
FROM prestations
GROUP BY prsPfiID_fk
ORDER BY COUNT(*) DESC
#+end_src                                             <<< org-block-end-line

Not only for =src=, but also for =verse=, =quote=, etc.

This patch takes care of the correct fontification, both in native style, and
in the "no native fontification" style: