[Pgbuildfarm-members] enhancement: filter files that can trigger a build

I committed changes today that allow filtering which files will trigger
a build. This is in version 1.18 of run_build.pl. Using that run file,
you can set a configuration parameter specifying a pattern of files to
ignore when considering if anything has changed. The recommended pattern
is: qr[/(doc|po)/] which will ignore any file in a doc or po directory.
Using that, if all we see is a doc or a po change, we won't do a build,
but if we see some other chnage we will. Doc and po file changes would
still be reported when the build is actually done.

I haven't cut a new release yet, but as always you can get the latest
version(s) from the CVS repo on pgfoundry.

cheers

andrew