Merge intrusive documentation fixes.
Merged revisions 50755 via svnmerge from https://svn.boost.org/svn/boost/trunk
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r50755 | danieljames | 2009-01-24 16:53:03 +0000 (Sat, 24 Jan 2009) | 3 lines
Documentation fixes for intrusive: restore the reference documentation and fix some spelling mistakes.