Merged from trunk -r15438:15449

   Merged from trunk -r15438:15449

   | 15445   | Add missing writmsg import.                                  |
   | zmedico |                                                              |

   | 15446   | Fix a logic error which causes blockers from installed       |
   | zmedico | packages to be ignored in some cases. Thanks to Brian Dolbec |
   |         | (dol-sen) for reporting.                                     |

   | 15447   | Remove unused 'expandcache' global variable.                 |
   | zmedico |                                                              |

   | 15448   | Split doebuild and related code to the                       |
   | zmedico | portage.package.ebuild module.                               |

   | 15449   | Make auxdbkeys a tuple instead of a list.                    |
   | zmedico |                                                              |

svn path=/main/branches/prefix/; revision=15478