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Module works fine on RHEL5 and RHEL6 in my tests
Make sure we can specify an entity more than once

Previously, one could only use and entity once. For at least the 'ALL' entity
however, we should be able to use this on more than one line.

For example, to allow logins only from my.safe.server, and deny login from all
other locations, we can now use:

+:ALL:my.safe.server
-:ALL:ALL