Introduce tentative API between UI and application engine
Merge pull request #123 from sortega/feature/api

Introduce tentative API between UI and application engine
Fix some API details
Use different cakes for peers and brokers on integration tests

Also, move all the code in coinffeine-test to the test/ source root.
Initialize PeerSupervisorActor from configuration
Add actor coordination test
Simplify PeerSupervisorActor and PeerActor into one

And extract the behavior of requesting quotes to a specialized actor
QuoteRequestActor and add missing tests to the moved code.
Introduce a partial implementation of CoinffeineApp

It just make it pass the enabled integration test. More to come.
Improve readability of AcceptanceTest class
Merge pull request #124 from sortega/feature/acceptance

Introduce a partial implementation of CoinffeineApp
Merge pull request #125 from edrevo/add-actor-coordination-test

Add actor coordination test
Implement connect() in DefaultCoinffeineNetwork
Merge pull request #127 from sortega/feature/network-connect

Implement connect() in DefaultCoinffeineNetwork
Introduce versioning in the protocol

Use the simplest criterium when parsing messages: rejecting messages with any version
other than the current one.
Merge pull request #129 from sortega/feature/versioning

Introduce versioning in the protocol
Add mock payment processor for testing
Refactor the exchange class to make it consistent with the Handshake class
Implement DefaultExchange
PR feedback
Merge pull request #133 from edrevo/implement-exchange

Implement exchange