pgbuildfarm - client-code: Sanity check for cvs merge conflicts.

Log Message:
-----------
Sanity check for cvs merge conflicts. This should not normally happen
but if people monkey with the source dir (e.g. by doing configure or build
in it, and expecially if they test their changes there instead of in a copy,
this can happen. CVS at least on some systems doesn't exit with failure
in such cases, so we look for the status lines that give it away.

Modified Files:
--------------
    client-code:
        run_build.pl (r1.43 -> r1.44)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgbuildfarm/client-code/run_build.pl.diff?r1=1.43&r2=1.44)