PHP-1063: Refactor cursor logic to follow MongoCommandCursor

https://jira.mongodb.org/browse/PHP-1063
You couldn't rely on the value at all. As for the last two the number was the same. I guess I could add one to the *output* (and not the internal structures), but I am not sure whether we should, as it's not representative of what's happening.

I've updated the 32bit test to be the same as the 64 bit one though.