[Enhancement] Add hashing database for known files

[TheRogueArchivist]

For files that are commonly used on many different discs (for example, DirextX installers), it may be a good idea to create a database of these files that definitely don't contain any protection, and hash the folder containing them (or even the individual files if it's still worth it) based on the name.

[JohnVeness]

I was going to suggest this too. Some discs have multiple versions of DirectX installers present, which take a long time to scan.

I was wondering if something could be done with the digital signatures already present on these files?