Base PoS functionality

[liamsi]

Using a minimal set modules define a minimalistic proof-of-stake application. This will provide the binary to (later) run a lazyledger node.

The application can live in this repository (e.g. in a sub-directory).

If it makes sense we could even use some scaffolding tool to create the app and use the replace directive in go.mod to point to the ../cosmos-sdk parent folder.

Even if this means deviating from the lazyledger spec, we want a first version that uses the existing cosmos-sdk module logic as much as possible. In fact, all transactions besides PayForMessage (#4) can be assumed to already exist in the SDK.

[liamsi]

This is addressed in https://github.com/lazyledger/lazyledger-app

Before we close this, we should probably make sure to:

• resolve all dependency issues (dependency: remove iavl celestia-core#129, Remove cosmos/iavl from lazyledger-core to stop dependency graph cycle celestia-core#128) update the app to use the updated version of ll-core and the sdk fork
• more thorough review (@liamsi)
• do manually test-run the node ((ll-app) and see if everything works as expected
• add CI (Add CI via github actions celestia-app#3)

[liamsi]

do manually test-run the node ((ll-app) and see if everything works as expected
add CI (celestiaorg/celestia-app#3)

@evan-forbes you tried this, right?

[liamsi]

Closing this as the base PoS functionality was included in https://github.com/lazyledger/lazyledger-app