pgsql: Don't elide blank lines when accumulating psql command history.

Don't elide blank lines when accumulating psql command history.

This can change the meaning of queries, if the blank line happens to
occur in the middle of a quoted literal, as per complaint from Tomas Vondra.

Back-patch to all supported branches.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/ff4fd4bf53c5512427f8ecea08d6ca7777efa2c5

Modified Files
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src/bin/psql/input.c |    4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)