Create initial 08-wasm Ethereum Light Client

[gjermundgaraba]

Get a basic version of the light client working and integrated into the repo.

Definition of done:

• Integrated into the current cargo workspace
• Basic project structure
• Working 08-wasm light client implementation (in that it can be deployed and will accept the messages from the 08-wasm go light client module)
• Implemented the core logic for membership proofs and verifying updates
  • Some testing that proves that it works correctly (ideally with fixtures from the e2e tests)
• Basic CI pipeline that builds and runs unit tests

What will not be covered here:

• Perfectly clean code
• Documentation
• Fully functional 08-wasm light client contract (we are focusing on the light client logic, not the contract integration points)
• Integration into the e2e tests