pgsql: Add FORCE_NOT_NULL support to the file_fdw foreign data wrapper.

Add FORCE_NOT_NULL support to the file_fdw foreign data wrapper.

This is implemented as a per-column boolean option, rather than trying
to match COPY's convention of a single option listing the column names.

Shigeru Hanada, reviewed by KaiGai Kohei

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/86a3f2d492f19da1f4be8ba099747ac5c83c43bb

Modified Files
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contrib/file_fdw/data/text.csv | 4 +
contrib/file_fdw/file_fdw.c | 112 +++++++++++++++++++++++++++++--
contrib/file_fdw/input/file_fdw.source | 16 +++++
contrib/file_fdw/output/file_fdw.source | 34 +++++++++-
doc/src/sgml/file-fdw.sgml | 31 ++++++++-
5 files changed, 185 insertions(+), 12 deletions(-)