Blocked revisions 71665 via svnmerge

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  r71665 | eric.smith | 2009-04-16 16:16:10 -0400 (Thu, 16 Apr 2009) | 14 lines

  The other half of Issue #1580: use short float repr where possible.

  Addresses the float -> string conversion, using David Gay's code which
  was added in Mark Dickinson's checkin r71663.

  Also addresses these, which are intertwined with the short repr
  changes:

  - Issue #5772: format(1e100, '<') produces '1e+100', not '1.0e+100'
  - Issue #5515: 'n' formatting with commas no longer works poorly
      with leading zeros.
  - PEP 378 Format Specifier for Thousands Separator: implemented
      for floats.
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