snapshot - src: Fast refreshes only with 25% or less modified rows on

Log Message:
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Fast refreshes only with 25% or less modified rows on source.

Modified Files:
--------------
src/pl:
getRefreshMethod.pl (r1.2 -> r1.3)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/snapshot/src/pl/getRefreshMethod.pl.diff?r1=1.2&r2=1.3)