Support temporary lexicon and index column
Support temporary lexicon and index column

We shouldn't unlink temporary objects because grn_obj_unlink() for
a temporary object really runs grn_obj_close().

komainu8/groonga,komainu8/groonga,kenhys/groonga,naoa/groonga,naoa/groonga,groonga/groonga,komainu8/groonga,naoa/groonga,groonga/groonga,groonga/groonga,naoa/groonga,komainu8/groonga,naoa/groonga,komainu8/groonga,kenhys/groonga,groonga/groonga,naoa/groonga,groonga/groonga,groonga/groonga,kenhys/groonga,kenhys/groonga,komainu8/groonga,naoa/groonga,groonga/groonga,komainu8/groonga,kenhys/groonga,kenhys/groonga,kenhys/groonga,kenhys/groonga,naoa/groonga,groonga/groonga,komainu8/groonga