pgbuildfarm - client-code: Make keeping error trees more robust and

Log Message:
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Make keeping error trees more robust and Windows-proof.

Modified Files:
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client-code:
run_build.pl (r1.79 -> r1.80)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgbuildfarm/client-code/run_build.pl.diff?r1=1.79&r2=1.80)