pgsql: Editorialize a bit on new ProcessUtility() API.

Editorialize a bit on new ProcessUtility() API.

Choose a saner ordering of parameters (adding a new input param after
the output params seemed a bit random), update the function's header
comment to match reality (cmon folks, is this really that hard?),
get rid of useless and sloppily-defined distinction between
PROCESS_UTILITY_SUBCOMMAND and PROCESS_UTILITY_GENERATED.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/f8db76e875099e5e49f5cd729a673e84c0b0471b

Modified Files
--------------
contrib/pg_stat_statements/pg_stat_statements.c |   31 ++++++-----
contrib/sepgsql/hooks.c                         |   14 +++--
src/backend/commands/extension.c                |    4 +-
src/backend/commands/schemacmds.c               |    4 +-
src/backend/commands/trigger.c                  |    3 +-
src/backend/executor/functions.c                |    4 +-
src/backend/executor/spi.c                      |    4 +-
src/backend/tcop/pquery.c                       |    5 +-
src/backend/tcop/utility.c                      |   62 +++++++++++++----------
src/include/tcop/utility.h                      |   17 +++---
10 files changed, 80 insertions(+), 68 deletions(-)