Integrate indy vdr

[ntsbs]

Short description of what this resolves:

This adds a Hyperledger Indy-VDR integration for AF .NET. Interfaces were minimally adjusted to handle different pool and request handles.

Changes proposed in this pull request:

• Adds DefaultPoolServiceV2, DefaultLedgerServiceV2 and DefaultSingingService
• Indy-sdk types were redacted from the interfaces
• Builder extensions AddAriesFrameworkV2 will add the Indy-VDR compliant services
• Integration tests for LedgerService and SchemaService included