Version Control With Subversion Source

* src/en/book/ch00.xml (svn.preface): Use <attribution> in <blockquote>
instead of writing it inline.

Book Spanish. Translated one paragraph.

- Added a section about NIGHTLY BUILDS.
- Translation status update.

Translation status update.

Fix the two remaining validation errors in the Italian web page,
duplicated id.

* www/index.it.html: Add class="translationstatus" to the translation
status table and change id= to class= in the two columns inside it.

* www/styles.css: Change "#translationstatus" to ".translationstatus".

* www/index.pt_BR.html: This file also uses a almost similar translation
status table, so add class="translationstatus" to it.

* www/index.it.html: Fixed various validation errors + changed <title>
content to Italian. Still two errors left, duplicated id in line 149
and 190. I’ll have a look at it now that the other stuff is out of
the way.

* src/tools/build-nightlies: Send alert emails when a build fails.

* src/tools/build-nightlies: Include a run of 'make valid' in the nightly
builds, so that invalid XML will cause the nightly build to fail.
Re-work the log code, so that it does not slurp the entire output into
memory, and only then write it into the log file. Instead, attempt to
make it work on a line-by-line basis so that tailing the logfiles is
somewhat possible.

* src/it/book/ch03.xml: Fix 5 separate instances of breakage in this file.

* src/zh/book/ch05.xml:
Fix up bogus xref linkend from the old numeric style (svn-ch-5-sect-2.2)
to the current named style (svn.reposadmin.create.bdb).