deny-updates - trunk: Add allow_on_condition function to allow trigger

Log Message:
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Add allow_on_condition function to allow trigger actions only if a user-specified condition is true. Update tests and
README.

Modified Files:
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    trunk/trunk:
        Makefile (r1.1.1.1 -> r1.2)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/deny-updates/trunk/trunk/Makefile?r1=1.1.1.1&r2=1.2)
        README (r1.4 -> r1.5)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/deny-updates/trunk/trunk/README?r1=1.4&r2=1.5)

Added Files:
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    trunk/trunk:
        allow_on_condition.sql (r1.1)

(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/deny-updates/trunk/trunk/allow_on_condition.sql?rev=1.1&content-type=text/x-cvsweb-markup)
    trunk/trunk/expected:
        allow_on_condition_test.out (r1.1)

(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/deny-updates/trunk/trunk/expected/allow_on_condition_test.out?rev=1.1&content-type=text/x-cvsweb-markup)
    trunk/trunk/sql:
        allow_on_condition_test.sql (r1.1)

(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/deny-updates/trunk/trunk/sql/allow_on_condition_test.sql?rev=1.1&content-type=text/x-cvsweb-markup)