pgsql: Make the pg_upgrade log files contain actual commands

Make the pg_upgrade log files contain actual commands

Now the log file not only contains the output from commands executed by
system(), but also what command it was in the first place.  This
arrangement makes debugging a lot simpler.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4741e9afb93f0d769655b2d18c2b73b86f281010

Modified Files
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contrib/pg_upgrade/exec.c |   16 +++++++++++++---
1 files changed, 13 insertions(+), 3 deletions(-)