Blocked revisions 79660,79733 via svnmerge

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  r79660 | raymond.hettinger | 2010-04-03 13:22:00 +0300 (Sat, 03 Apr 2010) | 1 line

  Add subtract() method to collections.Counter() objects.
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  r79733 | ezio.melotti | 2010-04-04 09:41:27 +0300 (Sun, 04 Apr 2010) | 1 line

  Add a versionadded to Counter.subtract() doc.
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