Add counters object storage implementation #51
Description
The Minio stack should support the statistics/counters related to GET/PUT requests and bytes at the minimum. This should be good for billing
Good to have few more metrics related to
- DEL requests
- Cluster capacity (available/free/total)
- node disk latency
- node disk capacity(avail/free/total)
- node_disk_status (online/offline)
- node status in the cluster (online/offline)