Cosmos SDK chain support in Unchained

Add support for cosmos and cosmos-sdk chains

Tech

• golang v1.17

Running

• Install golang
• Copy sample.launch.json to .vscode and update with any keys etc
• cmd/cosmos is main for Cosmos
• cmd/osmosis is main for Osmosis

Design

• The core functionality of chains like Osmosis and Thorchain is identical to Cosmos
• We can write the Cosmos SDK implementation once, and provide mechanisms to inject chain specific behavior (additional protos, support for custom messages and event logs, custom API routes etc)