MODCLUSTER-591 MemManagerFile should not default to server_root + "/l…

[rhusar]

…ogs"

[Karm]

@rhusar I'm not 100% convinced this is enough to make it better. Take a look into create_attach_mem_node and on, e.g. ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, 0, s, "get_mem_node %s failed", node); messages. It would be great if it suggests user using MemManagerFile to specify an existing directory... WDYT?

[Karm]

run tests

[jfclere]

actually the default httpd doesn't have cache, so the fix doesn't look like a good idea.