mathlib

a285049b - chore(algebra/group_hom): rename `add_monoid.smul` to `nsmul` (#2861)

chore(algebra/group_hom): rename `add_monoid.smul` to `nsmul` (#2861) Also drop `•` as a notation for two `smul`s declared in this file, use `•ℕ` and `•ℤ` instead. This way one can immediately see that a lemma uses `nsmul`/`gsmul`, not `has_scalar.smul`.