Merged from trunk -r13831:13839

   Merged from trunk -r13831:13839

   | 13832   | For unsatisfied USE dependencies, do not backtrack if only   |
   | zmedico | USE have to change in order to be satisfied. Thanks to       |
   |         | Thomas Sachau <tommy@gentoo.org> fo reporting.               |

   | 13833   | For consistency with emake, add ${MAKEOPTS} ${EXTRA_EMAKE}   |
   | zmedico | to make arguments inside einstall. Also, force -j1 in order  |
   |         | to override any --jobs settings from MAKEOPTS. Thanks to     |
   |         | Diego Pettenò <flameeyes@gentoo.org> for the suggestion.    |

   | 13834   | Use readlines() to optimize performance. Thanks to Marat     |
   | zmedico | Radchenko <slonopotamusorama@gmail.com> for this patch from  |
   |         | bug #276813.                                                 |

   | 13835   | In _check_manifests(), skip uninstall operations.            |
   | zmedico |                                                              |

   | 13836   | Use codecs.open for unicode support in FileLoader.load().    |
   | zmedico |                                                              |

   | 13837   | In grablines(), specify encoding=sys.getdefaultencoding() in |
   | zmedico | the codecs.open() parameters, since otherwise readlines      |
   |         | doesn't return unicode (at least in some cases, observed     |
   |         | with python-2.6.2). Also, fix grabfile() to return unicode   |
   |         | when it normalizes whitespace.                               |

   | 13838   | Fix Scheduler bug: the scheduler was adding prefetcher even  |
   | volkmar | for uninstall tasks                                          |

   | 13839   | Make portage.listdir() and dbapi.cp_list() return unicode.   |
   | zmedico |                                                              |

svn path=/main/branches/prefix/; revision=13847