pgsql: pgbench progress with timestamp

pgbench progress with timestamp

This patch adds an option to replace the "time since pgbench run
started" with a Unix epoch timestamp in the progress report so that,
for instance, it is easier to compare timelines with pgsql log

Fabien COELHO <coelho(at)cri(dot)ensmp(dot)fr>

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1def9063ca3c8ad66a2814a90af95ca22636bf66

Modified Files
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doc/src/sgml/ref/pgbench.sgml | 13 +++++++++++++
src/bin/pgbench/pgbench.c | 20 +++++++++++++++++---
2 files changed, 30 insertions(+), 3 deletions(-)