[Lightcone_V2.js] Migrate Lightcone v2 Javascript to Typescript (#247)

* Point DexService to aws hosted service

* Make lightcone_v2.js to import in react web app

* Update grpcClient.ts

* [Lightcone_V2.js] Migrate Lightcone v2 Javascript to Typescript (#244)

* Migrate lightcone v2 js to typescript (Step 1)

* Solve typesript errors in walletAccount.ts

* Resolve all errors during migration from Javascript to Typescript.

* Move tests to typescript in lightcone_v2.js

* Add resolveJsonModule to true. Update index.js which is the entrypoint of the package.

* Add GetNextOrderIdReq to test importing grpc . Reenable test/grpc.ts

* Update grpcClient

Author: xiaowheat