pgsql: Allow the low level COPY routines to read arbitrary numbers of f

Allow the low level COPY routines to read arbitrary numbers of fields.
This doesn't involve any user-visible change in behavior, but will be
useful when the COPY routines are exposed to allow their use by Foreign
Data Wrapper routines, which will be able to use these routines to read
irregular CSV files, for example.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=af1a614ec6d074fdea46de2e1c462f23fc7ddc6f

Modified Files
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src/backend/commands/copy.c | 93 ++++++++++++++++++++++++++----------------
1 files changed, 57 insertions(+), 36 deletions(-)