AB axioms for the category of abelian groups #
This file proves that the category of abelian groups satisfies Grothendieck's axioms AB5, AB4, and AB4*.
instance instAdditiveFunctorColim {J : Type u_1} {C : Type u_2} [CategoryTheory.Category.{v_1, u_1} J] [CategoryTheory.Category.{v_2, u_2} C] [CategoryTheory.Limits.HasColimitsOfShape J C] [CategoryTheory.Preadditive C] :