#2775 - Adding migration guide for waiting on promises
Unwatch watched actors on termination. Fixes: #2923

unwatchWatchedActors must stay in finishTerminate as an emergency stop might occur at handleInvokeFailure
added basic support for Epub generation
Merge pull request #1041 from RickLatrine/wip-2923-terminated-cascade-ricklatrine

Prevents Terminated message cascade, see #2923
Merge pull request #1046 from tlockney/feature/epub-support

added basic support for Epub generation