Blocked revisions 68850,68853 via svnmerge

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  r68850 | raymond.hettinger | 2009-01-21 23:20:47 -0600 (Wed, 21 Jan 2009) | 1 line

  More doc tweaks.
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  r68853 | raymond.hettinger | 2009-01-22 03:05:43 -0600 (Thu, 22 Jan 2009) | 1 line

  Update comments and add an optimized path for Counter.update().
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