Merged from trunk -r15421:15429

   Merged from trunk -r15421:15429

   | 15422    | Move the portage.util module into a directory, for          |
   | zmedico  | splitting into smaller files.                               |

   | 15423    | Move portage.digraph class to portage.util.digraph.digraph. |
   | zmedico  |                                                             |

   | 15424    | Move portage.config class to                                |
   | zmedico  | portage.package.ebuild.config.config.                       |

   | 15425    | Move portage.fetch() to                                     |
   | zmedico  | portage.package.ebuild.fetch.fetch().                       |

   | 15426    | Use lazy import for portage.Manifest.                       |
   | zmedico  |                                                             |

   | 15427    | Enable --rebuilt-binaries automatically only when in        |
   | zmedico  | --usepkgonly or --getbinpkgonly mode, since --usepkgonly    |
   |          | behaves better in cases when the portage tree is not        |
   |          | exactly the same revision that was used to build the        |
   |          | packages.                                                   |

   | 15428    | Fix "NameError: global name 'basestring' is not defined"    |
   | arfrever | with Python 3.                                              |

   | 15429    | Fix "AttributeError: 'module' object has no attribute       |
   | arfrever | 'mappings'". Also fix some typos.                           |

svn path=/main/branches/prefix/; revision=15434