Goal:
  
  A : Type
  P : A → Prop
  l1 : list A
  l2 : list A
  h1 : Forall P l1
  h2 : Forall P l2
  ============================
   (Forall P (l1 ++ l2))


DEBUG:Going to execute:
<coq-core.plugins.ltac::revert@0> $1