Add comments 10 and 8 from the servers of happiness spec
Fix bug in _filter_g3 for servers of happiness
Remove usage of HappinessUpload class
here we modifying the PeerSelector class.
we make sure to correctly calculate the happiness value
by ignoring keys who's value are None...
Remove HappinessUpload and tests
Replace helper servers_of_happiness
we replace it's previous implementation with a new
wrapper function that uses share_placement