Merged revisions 77212-77215 via svnmerge from

Merged revisions 77212-77215 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r77212 | benjamin.peterson | 2010-01-01 09:16:29 -0600 (Fri, 01 Jan 2010) | 1 line

  use pkg-config to find the libffi headers when --with-system-ffi is used #6943
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  r77213 | benjamin.peterson | 2010-01-01 09:18:38 -0600 (Fri, 01 Jan 2010) | 1 line

  add note
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  r77214 | benjamin.peterson | 2010-01-01 09:20:06 -0600 (Fri, 01 Jan 2010) | 1 line

  fix indentation
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  r77215 | benjamin.peterson | 2010-01-01 09:21:13 -0600 (Fri, 01 Jan 2010) | 1 line

  allow --with-dbmliborder to specify that no dbm modules will be built #6491
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