All Key-Value Tables must be accessed via the APIs in io.pravega.client.tables

[shshashwat]

Problem description
Currently Schema Registry is using wire-commands directly to the segment-store. This needs to be changed and the implementation should be to use Client API instead of Wire-Commands since Schema Registry is a separate service from Pravega.

Problem location
Across the repo

Suggestions for an improvement
Remove every wire-commands and implement it via KVT Client API.