default_site_preference so testDmsWithFlare does nothing more than
testDms.
Now, preferred_cache_cache_factory is set to "dms_cache_factory"
which enable flare as memcached backend.



git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@31252 20353a03-c40f-0410-a6d1-a30d3c3de9de