This test fails with a weird segfault somewhere in the engine on PHP 5.2

Since its on PHP 5.2 which noone cares about anyway we stick our head in
the ground and pretend it doesn't exist
Merged pull request #504
Move the node type discovery into the first ismaster call (get_server_flags)
Fixed PHP-392 and PHP-844

This is a regression introduced in 1.3.x.
Arbiters do not contain any data and we should not be trying to login to
them.