Merge pull request #4886 from owncloud/public_cache

lib/base.php

lib/cache.php

lib/cache/broker.php

lib/cache/file.php

lib/cache/fileglobal.php

lib/cache/fileglobalgc.php

lib/cache/usercache.php

lib/filechunking.php

lib/legacy/cache.php

lib/public/icache.php

lib/public/iservercontainer.php

lib/server.php

tests/lib/cache.php

tests/lib/cache/file.php

tests/lib/cache/usercache.php