[evol] Protocol: allow returning multiple errors
[fix] Protocol: typo leading to error result not detected
[evol] Cyborg/Interface: support returning API call replies asynchronously
[licence] updated copyright years
[evol] Protocol/Interface: don't check for existence before node call, it is already done in call and a loss of time
[fix] method name mistake
[fix] Protocol: check node existence asynchronously for CALL
[evol] Protocol/DSL: implemented node existence check
[evol] server API tree reworked using a DSL (reply handling rework is WIP)
[layout] reorganization