merge of cmake build files from trunk per beman

svn path=/branches/release/libs/iostreams/; revision=50756
Merged revisions 45283,48266 via svnmerge from 
https://svn.boost.org/svn/boost/trunk

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  r45283 | danieljames | 2008-05-11 14:49:20 +0100 (Sun, 11 May 2008) | 1 line
  
  Quote href values - our tools don't support unquoted values.
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  r48266 | danieljames | 2008-08-20 20:32:23 +0100 (Wed, 20 Aug 2008) | 1 line
  
  Fix the link to the limits documentation.
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svn path=/branches/release/libs/iostreams/; revision=51902