WIP API changes, with technically passing tests

api/client.go

api/notifications.go

api/utilsInterfaces_test.go

api/utils_test.go

auth/confirm.go

auth/request.go

auth/state.go

cmix/client.go

cmix/message/pickup.go

cmix/params.go

cmix/rounds/historical.go

cmix/sendCmix.go

cmix/sendManyCmix.go

dummy/utils_test.go

e2e/manager.go

e2e/params.go

e2e/rekey/rekey.go

event/event.go

event/event_test.go

event/interface.go