pginstaller - pginst: Exclude by regexp instead of filename.

Log Message:
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Exclude by regexp instead of filename. Add option to include/exclude based on filename regexps.
Gives some more flexibility to the WXI generation steps.

Modified Files:
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pginst/util:
builddir.pl (r1.4 -> r1.5)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pginstaller/pginst/util/builddir.pl.diff?r1=1.4&r2=1.5)