Merged from trunk 8400:8418

   Merged from trunk 8400:8418

   | 8401     | Bug #197965 - When fetch() encounters a checksum failure,   |
   | zmedico  | look for an identical file from a previous checksum failure |
   |          | in order to avoid consuming unnecessary disk space with     |
   |          | duplicate files.                                            |

   | 8402     | if mode=1 and `dialog` is not usable, abort #197990 by      |
   | SpankMan | DominikBuerkle                                              |

   | 8403     | Bug #197965 - Make fetch() bail out after 5 checksum        |
   | zmedico  | failures for a particular file since downloading the same   |
   |          | file repeatedly from every single available mirror is a     |
   |          | waste of bandwidth and time.                                |

   | 8405     | Call die() so that the $TMP directory is always properly    |
   | zmedico  | cleaned up.                                                 |

   | 8408     | Bug #197797 - Do not actively clear o+rx permission bits on |
   | zmedico  | the /var/lib/portage directory. Only clear the o+w bits.    |
   |          | This allows users who aren't in the portage group to have   |
   |          | read access to the world file by default, but               |
   |          | administrators can explicitly chmod o-rx that directory if  |
   |          | necessary, and portage will leave those bits alone. This    |
   |          | makes the permission settings in dblink.treewalk()          |
   |          | consistent with those that are already defined in           |
   |          | config._init_dirs().                                        |

   | 8410     | For sanity, pass an actual list of keys into aux_get()      |
   | zmedico  | instead of iterating over a set that happens to be mutable  |
   |          | (though it remains constant in practice).                   |

   | 8412     | Make fetch() behave like the ebuild has                     |
   | zmedico  | RESTRICT="primaryuri" after 2 checksum failures for a       |
   |          | fetched file. This should increase the probability of       |
   |          | fetching the correct file before the maximum number of      |
   |          | tries is reached.                                           |

   | 8414     | Generate a usage.obsolete warning whenever -* is found in   |
   | zmedico  | KEYWORDS.                                                   |

   | 8416     | In fetch(), replace checksum_failure_counts dict with       |
   | zmedico  | single int counter.                                         |

   | 8418     | Clean up ACCEPT_KEYWORDS incremental stacking logic and fix |
   | zmedico  | some minor inconsistencies.                                 |

svn path=/main/branches/prefix/; revision=8434