[pgpool-committers: 4825] pgpool: Implement cross-pgpool query cache invalidation.

[Tatsuo Ishii]

Implement cross-pgpool query cache invalidation.

Todo:
- Drop database case
- Documents
- Tests

Branch
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query_cache

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=52cfbb637f798cdd08872dd36b7e2366a74dde4d

Modified Files
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src/include/query_cache/pool_memqcache.h |   3 -
src/query_cache/pool_memqcache.c         |  86 +++++----
src/query_cache/pool_oid_map.c           | 291 ++++++++++++++++++++++++++++++-
3 files changed, 339 insertions(+), 41 deletions(-)