Added

autostart config parameter to allow generation to be paused on startup (set to false)
total expected chunk count to list command
config parameters related to the unloading task

Changed

requesting chunk generation to be done in a different thread and therefore not blocking the main thread
chunk unloading to be done in a different context than the generation
generation to have several stages
- seek: finds the first chunk that hasn't been generated yet
- generate: generates until the end of the task is reached
- validate: validates that all chunks have been generated
- correct: generates all chunks that are missing
database to be accessed by DAOs only
generation tasks to only have one task that handles both paper and spigot (by using PaperLib)
table to store chunks that were pending when the server was stopped or were not generated when validating