Merged from trunk 7621:7639

   Merged from trunk 7621:7639

   | 7622     | Add some floating point vercmp cases.                       |
   | zmedico  |                                                             |

   | 7625     | Always assign higher priority to dependencies on packages   |
   | zmedico  | that are being rebuilt (except when --emptytree is enabled  |
   |          | since all packages are merged in that case). This optimizes |
   |          | merge order so that dependencies are rebuilt/updated as     |
   |          | soon as possible.                                           |

   | 7627     | Combine 2 locations in depgraph.create() where nodes are    |
   | zmedico  | added to the digraph. This ensures that dependencies on     |
   |          | "rebuild" nodes always have their priority increased.       |

   | 7628     | Fix existing_node logic inside depgraph.create().           |
   | zmedico  |                                                             |

   | 7632     | make -f/-F distinction clearer                              |
   | SpankMan |                                                             |

   | 7636     | Make etc-update copy owner and group bits when it merges    |
   | zmedico  | config files.                                               |

   | 7639     | For bug #189219, use pkgcmp() to sort versions in           |
   | zmedico  | selected/protected/omitted unmerge display.                 |

svn path=/main/branches/prefix/; revision=7642