Merged from trunk -r12425:12492

   Merged from trunk -r12425:12492

   | 12426   | Fix a TypeError which occurs in pretend commit mode when vcs |
   | zmedico | is None. Thanks to Fabian Groffen <grobian@g.o> for          |
   |         | reporting.                                                   |

   | 12427   | Make the greedy slot atom code from bug #150361 look ahead   |
   | zmedico | for conflicts between the packages that will be pulled in.   |
   |         | If a conflict is discovered, drop the greedy slot atom for   |
   |         | the older slot. This solves a problem reported by kde4 users |
   |         | when running `emerge -u ` for a package that has the         |
   |         | kdeprefix flag disabled. In this case, the newer slot blocks |
   |         | the older slot. In order to allow the older slot to be       |
   |         | automatically uninstalled, the atom for the older slot needs |
   |         | to be excluded from the graph. Thanks to Maciej Mrozowski    |
   |         | for testing this patch.                                      |

   | 12428   | Bug #241808 - When loading options for --resume, discard the |
   | zmedico | --color option so it doesn't override the current setting.   |

   | 12429   | Fix comment about the greedy slots code.                     |
   | zmedico |                                                              |

   | 12484   | Invalidate some more caches inside depgraph._set_args().     |
   | zmedico |                                                              |

   | 12486   | When checking for conflicts between packages inside          |
   | zmedico | depgraph._greedy_slots(), never double-check any of the      |
   |         | pairs.                                                       |

   | 12488   | Mention the blocker_lookahead parameter in the               |
   | zmedico | depgraph._greedy_slots() docstring.                          |

   | 12490   | When selecting greedy package inside                         |
   | zmedico | depgraph._greedy_slots(), make sure the selected packages    |
   |         | have the same cp as the highest selected version.            |

svn path=/main/branches/prefix/; revision=12525