What are you trying to do?

When working on implementations, I always get a bit confused whether to use the name "pack"/"pack file" or "data file".

In the users documentation part "Terminology", it is referred as "Packs", but the dir in the repository layout is /data.

Also, in the implementations, the constant is called DataFile which may be mixed up with DataBlob but I've seen may places where variables/comments or user outputs refer to "packs".

I suggest to:

• change DataFile into PackFile
• look for "data file" et al in code/comments and change if necessary
• add an explanation in resign.rst that packs are stored under /data for historic reasons

Is this a common view? I can prepare an PR if we agree that this clarifies things.