Document 'boost:' links in boostbook & quickbook.

Merged revisions 52352 via svnmerge from 
https://svn.boost.org/svn/boost/trunk

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  r52352 | danieljames | 2009-04-12 12:21:59 +0100 (Sun, 12 Apr 2009) | 3 lines
  
  Document 'boost:' links in boostbook & quickbook.
  
  Fixes #2861.
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[SVN r52398]

tools/boostbook

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-Subproject commit 1df2cadc32c61baebad11dabb6d09926057ca5df
+Subproject commit 5e38276d2396787a0ce463fee177e8bc2d3c71dd

tools/quickbook

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-Subproject commit 2da89ae716d34aa1812788dcd5cb08d94857e360
+Subproject commit 4078431c29324cb960d06a08e7e992980f38b35e