Add support for native/ibc tokens and inline messages

[josefleventon]

Adds support for:

• Any native or IBC token to be included in a trade offer (only from the sender)
• Creator royalties to be fairly paid out for each native or IBC token included in the trade
• Optional inline messages to be used for identification or other generic purposes

Todo:

• Integration tests (🙆‍♂️🔫)
• Unit tests
• Documentation