[ Chris Lamb ]
* Don't duplicate file lists at each directory level.
  (Closes: #989192, reproducible-builds/diffoscope#263)
* When pretty-printing JSON, mark the difference as such, additionally
  avoiding including the full path.
  (Closes: reproducible-builds/diffoscope#205)

* Codebase improvements:
  - Update a bunch of %-style string interpolations into f-strings or
    str.format.
  - Import itertools top-level directly.
  - Drop some unused imports.
  - Use isinstance(...) over type(...) ==
  - Avoid aliasing variables if we aren't going to use them.

[ Brandon Maier ]
* Fix missing diff output on large diffs.

[ Mattia Rizzolo ]
* Ignore a Python warning coming from a dependent library (triggered by
  supporting Python 3.10)
* Document that support both Python 3.9 and 3.10.