Merged from trunk 10359:10377

   Merged from trunk 10359:10377

   | 10360   | Tweak vardbapi.aux_get() cache logic a bit.                  |
   | zmedico |                                                              |

   | 10361   | In unmerge(), flush the vardbapi aux_get() cache to disk     |
   | zmedico | before releasing the vardb lock.                             |

   | 10364   | Exclude "env" from use in variable substitution since we     |
   | zmedico | want to avoid any interaction with the calling environment   |
   |         | that might lead to unexpected results.                       |

   | 10367   | Fix vardbapi.aux_get() logic so that it will correctly pull  |
   | zmedico | the metadata value corresponding to an unrecognized metadata |
   |         | key.                                                         |

   | 10369   | Validate and normalize target_root earlier in the config     |
   | zmedico | constructor.                                                 |

   | 10372   | Adjust code order to organize it a bit. (branches/2.1.2      |
   | zmedico | r10371)                                                      |

   | 10373   | Inside vardbapi.aux_get(), do more validation on the cache   |
   | zmedico | data to ensure it contains the expected data types.          |

   | 10375   | In vardbapi.aux_get(), don't mark cacheed metadata invalid   |
   | zmedico | just because some of the values are missing.                 |

   | 10377   | Simplify cache code in vardbapi.aux_get().                   |
   | zmedico |                                                              |

svn path=/main/branches/prefix/; revision=10385