Orchestration API support of NFTs

[Jorge-Lopes]

refs: #33

Description

This PR aims to extend the Agoric Orchestration package to support the cosmos NFT module, more specifically, providing a kit that exposes methods to:

• query all NFTs held on an Interchain Account
• query all NFTs from a specific Class held on an Interchain Account
• transfer the NFT to other address in that chain

In order to implement the methods above, it is necessary to:

• convert the NFT into an ERTP asset
• map a defined denom that identifies the Class and host chain with the local Issuer and Brand objects

Note: based on the commit e436743, it is reasonable to assume that the NftKit features may be implemented under the cosmosOrchestrationAccount instead of a dedicated exo-kit.

Security Considerations

To be done ...

Documentation Considerations

For a better perception of the changes implemented, we advise to generate the api spec of the Orchestration package:

yarn install && yarn build
cd packages/orchestration
yarn typedoc
open docs/index.html

At the issue #33, a description of the logic behind the changes implemented can be found with the support of diagrams.

Testing Considerations

To be done ...

Upgrade Considerations

To be done ...