Correct boost.url.prefix for htmlhelp and add a link to test it.

[SVN r51322]

doc/test/Jamfile.v2

@@ -198,7 +198,7 @@ boostbook standalone
         # HTML Help Options:
         #======================================================================
         #<format>htmlhelp:<xsl:param>img.src.path=../html
-        <format>htmlhelp:<xsl:param>boost.url.prefix=http://www.boost.org/doc/libs/release/doc/pdf/htmlhelp
+        <format>htmlhelp:<xsl:param>boost.url.prefix=http://www.boost.org/doc/libs/release/doc/test/html
         <format>htmlhelp:<xsl:param>htmlhelp.chm=test.chm
     ;
 

doc/test/test.qbk

@@ -384,6 +384,10 @@ it should be rewritten to point to the website when building a PDF.
 This is [@boost:/libs/regex/index.html a link to another library's documentation (Boost.Regex)], using the boost:/ protocol,
 it should be rewritten to point to the website when building a PDF.
 
+This is [@../weighted_tail_quantile.hpp a relative link to a header file within the test source],
+it should be rewritten to point to the website when building a PDF.
+Although it might be on the website yet.
+
 [endsect]
 
 [section Footnotes]