pgsql: Add -D option to specify data directory to pg_controldata and pg

Add -D option to specify data directory to pg_controldata and pg_resetxlog.

It was confusing that to other commands, like initdb and postgres, you would
pass the data directory with "-D datadir", but pg_controldata and
pg_resetxlog would take just plain path, without the "-D". With this patch,
pg_controldata and pg_resetxlog also accept "-D datadir".

Abhijit Menon-Sen, with minor kibitzing by me

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/b0d81adea650a4bc2b9391234345bb935b89a694

Modified Files
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doc/src/sgml/ref/pg_controldata.sgml | 2 +-
doc/src/sgml/ref/pg_resetxlog.sgml | 2 +-
src/bin/pg_controldata/pg_controldata.c | 2 +-
src/bin/pg_resetxlog/pg_resetxlog.c | 16 ++++++++++------
4 files changed, 13 insertions(+), 9 deletions(-)