Merged revisions 77589 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r77589 | mark.dickinson | 2010-01-17 20:57:56 +0000 (Sun, 17 Jan 2010) | 7 lines

  Issue #7632: When Py_USING_MEMORY_DEBUGGER is defined, disable the
  private memory allocation scheme in dtoa.c, along with a piece of code
  that caches powers of 5 for future use.  This makes it easier to
  detect dtoa.c memory leaks with Valgrind or similar tools.

  Patch by Stefan Krah.
........