pgsql: Refactor ALTER some-obj RENAME implementation

Refactor ALTER some-obj RENAME implementation

Remove duplicate implementations of catalog munging and miscellaneous
privilege checks.  Instead rely on already existing data in
objectaddress.c to do the work.

Author: KaiGai Kohei, changes by me
Reviewed by: Robert Haas, Álvaro Herrera, Dimitri Fontaine

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/765cbfdc9263bf7c90b9d1f1044c6950b8b7088c

Modified Files
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src/backend/catalog/objectaddress.c         |    4 +-
src/backend/commands/aggregatecmds.c        |   63 -----
src/backend/commands/alter.c                |  374 ++++++++++++++++++++-------
src/backend/commands/collationcmds.c        |   48 ----
src/backend/commands/conversioncmds.c       |   53 ----
src/backend/commands/event_trigger.c        |   46 ----
src/backend/commands/foreigncmds.c          |   87 ------
src/backend/commands/functioncmds.c         |   61 +-----
src/backend/commands/opclasscmds.c          |  171 +++----------
src/backend/commands/proclang.c             |   42 ---
src/backend/commands/tsearchcmds.c          |  196 --------------
src/backend/parser/gram.y                   |   12 +-
src/include/commands/collationcmds.h        |    3 +-
src/include/commands/conversioncmds.h       |    1 -
src/include/commands/defrem.h               |   14 +-
src/include/commands/event_trigger.h        |    1 -
src/include/commands/proclang.h             |    1 -
src/test/regress/expected/alter_generic.out |   16 +-
src/test/regress/sql/alter_generic.sql      |    6 +-
19 files changed, 348 insertions(+), 851 deletions(-)