Backups, example improvements and refactors

[Jasonvdb]

• Improved the example app to demo more LND functions
• Exporting backups
• Subscribing to backup updates so app knows when to backup a new channel state
• Backup verification
• Native refactoring for both Swift and Java to not use protobuf for request/responses. All logic for decoding/encoding moved to typescript so any changes to the API going forward likely won't require any native updates. We also only need to maintain files generated from protos in typescript now instead of in 3 places.

[coreyphillips]

Receiving the following error:
error: Error: Unable to resolve module ./walletunlocker from /spectrum/node_modules/react-native-lightning/src/lnd.ts:

Looks like it's coming from this line specifically.

[Jasonvdb]

Did you run yarn build? It should be building the missing protobuf walletunlocker.d.ts file from the .proto 🤔

[coreyphillips]

I did, but it still seems to throw the same error. Going to experiment with the local build and see what's going on.

[Jasonvdb]

Ok committed the walletunlocker.d.ts for now. You'll still need to go into react-native-lightning and yarn build though