SLING-3364 - All rotated log files are not made part of the zip provided through webconsole

Added support which uses logic similar to one used in earlier Sling Log implementations whereby rotated files present in same directory would be included

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1571618 13f79535-47bb-0310-9956-ffa450edef68