Merged from trunk 10884:10892

   Merged from trunk 10884:10892

   | 10885   | * Rename existing EbuildBuild class to EbuildExecuter. *     |
   | zmedico | Split more code out of Scheduler._execute_task() and use it  |
   |         | to make a more comprehensive EbuildBuild class.              |

   | 10886   | Remove debugging code from the previous commit.              |
   | zmedico |                                                              |

   | 10887   | Split out a Binpkg class from code inside                    |
   | zmedico | Scheduler._execute_task().                                   |

   | 10888   | Fix inverted buildpkgonly logic.                             |
   | zmedico |                                                              |

   | 10889   | Fix EbuildBuild.execute() to return os.EX_OK on success.     |
   | zmedico |                                                              |

   | 10890   | Py3k compatibility patch by Ali Polatel <hawking@g.o>. Don't |
   | zmedico | use the format raise Exception, "string"                     |

   | 10891   | Split out a SubProcess base class for EbuildFetcherAsync,    |
   | zmedico | EbuildPhase, and BinpkgFetcherAsync.                         |

   | 10892   | Remove $PORTAGE_BUILDDIR locking from portage.pkgmerge() and |
   | zmedico | use an instance of EbuildBuildDir instead.                   |

svn path=/main/branches/prefix/; revision=10893