Adding azure provider implementation for schema service
These set of changes introduce azure implementation of schema service.
Testing
Unit tests have been added for required classes.
Integration tests: pending
What might change in future:
Data partitioning in azure cosmos db: currently data from all the tenants is being stored in a single cosmos db instance, partitioned by the dataPartitionId of that tenant. This model might change in future.
@danielscholl , @dkodeih FYI.