Problem: Tx decoder rejects unknown transaction types by default

[calvinaco]

Background

Each Cosmos-based chains may have included different modules onto the chain. In the current design the default behaviour upon unknown transaction types is to panic, which is good for development but produce unfriendly result to production.

Proposed Solution

• Provide default RegisterInterface for different chains (chains can also submit new PR to add their own Interfaces)
• Offer configs on decode error behaviour (panic or ignore)