Add caching of deleted and added jokes in submission script

[Sv443]

This is so the uniqueness score can continuously trained and its data persists.
Currently the memory of the uniqueness calculation is lost when the process exits, which isn't ideal.

Todo:

• [x] Create a cache file of deleted and added jokes
• [x] Oldest entries are cleared after x amount of time passed or file size > y
• [ ] Combine cache file contents and current uniqueness memory so the fuse.js fuzzy search can source both