Changes
Added w and wtimeout. GridFS: added get, put, and delete methods, index
checks on all methods, added fields param to GridFS::findOne. Fixed some
error messages (authentication and BSON deserialization) and handling (for
large messages and field names passed as integers). Fixed a couple of double
frees and an incorrect cursor boundry condition. Added MongoId::__set_state
and MongoId::getHostname (to see the hostname hashed for unique ids).