testcase_stats: install Apache config for indexing
    
    testcase_stats relies on the server to do directory indexing,
    it doesn't provide its own index files. We need to configure
    Apache to do directory indexing for the openQA public dir, and
    disable reverse proxying for it (apparently reverse proxying
    takes precedence over index generation).
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>