pgAgent commit: USe exit status macros to get the Unix exit code, and r

USe exit status macros to get the Unix exit code, and recognise all
non-zero return values as failure codes.

Per discussion with Korry Douglas and Robert Haas.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgagent.git;a=commitdiff;h=2aec3bc473e583f8fa07e133bc8def60ff1c09fe

Modified Files
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job.cpp |    9 ++++++---
1 files changed, 6 insertions(+), 3 deletions(-)