duckgrep 0.2.1

Changed

• Catching up after many files change is faster. After a branch switch, a big pull or a copied index, the next query re-indexes the changed files. Moving a django checkout 300 commits (698 files) now takes 5.8 s instead of 13.5 s, and a copied index on the same commit catches up in 0.6 s instead of 2.2 s.