[4suite] New sdocbook_html.xslt raises an error on 4Suite install

[Mike Brown]

Jeremy Kloth wrote:
> > What that %40 does?
> 
> In general, it prevents robots from scraping email addresses.  It is the 
> ordinal for '@'.

Correct. If you avoid exposing a raw '@' in email addresses on web pages,
it cuts down on spam. So, in the mailto link, use '%40', and in the text,
use '@'.

References:

   http://www.cdt.org/speech/spam/030319spamreport.shtml
   http://spam.weblogsinc.com/entry/1234000747035099/

The bug in 4XSLT was exposed when I modified sdocbook_html.xslt to obfuscate
raw email addresses like that, and to avoid generating links for
already-obfuscated addresses (like 'mike at skew.org').

The bug was that an attribute value template containing an XPath expression
(in curly braces) and a '%' outside of the braces would generate a traceback 
because the '%' was being interpreted as part of a format string.

I reported it on IRC last night, and filed a bug report on SourceForge.
Jeremy has already fixed it, as noted.

I don't know how long the bug has been in 4XSLT.

Mike