Resolve GIDs in the simple access provider
    
    Changes the simple access provider's interface to be asynchronous. When
    the simple access provider encounters a group that has gid, but no
    meaningful name, it attempts to resolve the name using the
    be_file_account_request function.
    
    Some providers (like the AD provider) might perform initgroups
    without resolving the group names. In order for the simple access
    provider to work correctly, we need to resolve the groups before
    performing the access check. In AD provider, the situation is
    even more tricky b/c the groups HAVE name, but their name
    attribute is set to SID and they are set as non-POSIX