After the addition of Storage Class support, readQuorum
and writeQuorum are decided on a per object basis, instead
of deployment wide static quorums.
This PR updates madmin api to remove readQuorum/writeQuorum
and add Standard storage class and reduced redundancy storage
class parity as return values. Since these parity values are
used to decide the quorum for each object.
Fixes#5378
Nitish Tiwari
Matthieu Paret
Anis Elleuch