pgsql: Cleanup slots during drop database

Cleanup slots during drop database

Automatically drop all logical replication slots associated with a
database when the database is dropped. Previously we threw an ERROR
if a slot existed. Now we throw ERROR only if a slot is active in
the database being dropped.

Craig Ringer

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/ff539da31691f2cd2694360250571c5c5fb7415e

Modified Files
--------------
doc/src/sgml/func.sgml                             |  3 +-
doc/src/sgml/protocol.sgml                         |  2 +
src/backend/commands/dbcommands.c                  | 32 +++++---
src/backend/replication/slot.c                     | 88 ++++++++++++++++++++++
src/include/replication/slot.h                     |  1 +
src/test/recovery/t/006_logical_decoding.pl        | 40 +++++++++-
.../recovery/t/010_logical_decoding_timelines.pl   | 30 +++++++-
7 files changed, 182 insertions(+), 14 deletions(-)