mathlib

0038a043 - feat(data/int/cast): int cast division lemmas (#13929)

feat(data/int/cast): int cast division lemmas (#13929) Adds lemmas for passing int cast through division, and renames the nat versions from `nat.cast_dvd` to `nat.cast_div`. Also some golf. Co-authored-by: Scott Morrison <scott.morrison@gmail.com>