Merged from trunk 8627:8640

   Merged from trunk 8627:8640

   | 8628    | Add support for persistence of colon separated               |
   | zmedico | SANDBOX_{DENY,READ,PREDICT,WRITE} variables between phases   |
   |         | so things like the global scope addpredict() call in         |
   |         | qt3.eclass will continue to work.                            |

   | 8629    | Filter _E_DOCDESTTREE_ and _E_EXEDESTTREE_ from              |
   | zmedico | environment.bz2.                                             |

   | 8630    | In the grep expression that's generated in                   |
   | zmedico | filter_readonly_variables(), condense redundant identical    |
   |         | expressions into a single one.                               |

   | 8634    | Fix the var_grep variable in filter_readonly_variables() so  |
   | zmedico | that it's properly local.                                    |

   | 8636    | Unconditionally filter some of the SANDBOX_* variables from  |
   | zmedico | the environment in order to avoid potential interference     |
   |         | problems. For example, having an invalid value for           |
   |         | SANDBOX_LOG prevents the sandbox from killing the ebuild     |
   |         | when a violation occurs.                                     |

   | 8638    | When binarytree.populate() finds missing metadata, specify   |
   | zmedico | which keys are missing so that the user has a clue about     |
   |         | what is wrong.                                               |

   | 8640    | Fix quoting to work properly with eval.                      |
   | zmedico |                                                              |

svn path=/main/branches/prefix/; revision=8642