pgsql: Support more locale-specific formatting options in cash_out().

Support more locale-specific formatting options in cash_out().

The POSIX spec defines locale fields for controlling the ordering of the
value, sign, and currency symbol in monetary output, but cash_out only
supported a small subset of these options. Fully implement p/n_sign_posn,
p/n_cs_precedes, and p/n_sep_by_space per spec. Fix up cash_in so that
it will accept all these format variants.

Also, make sure that thousands_sep is only inserted to the left of the
decimal point, as required by spec.

Per bug #6144 from Eduard Kracmar and discussion of bug #6277. This patch
includes some ideas from Alexander Lakhin's proposed patch, though it is
very different in detail.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/6743a878a4e9442a9846d8c270e5028e514d44f3

Modified Files
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src/backend/utils/adt/cash.c | 166 ++++++++++++++++++++++++++++++++++--------
1 files changed, 134 insertions(+), 32 deletions(-)