feat(library/init/ite_simp): add simp lemmas
feat(library/init/ite_simp): add simp lemmas

digama0/lean,leanprover-community/lean,dselsam/lean,leanprover-community/lean,dselsam/lean,leanprover/lean,leanprover-community/lean,leanprover/lean,Kha/lean,Kha/lean,Kha/lean,leanprover-community/lean,leodemoura/lean,Kha/lean,leanprover-community/lean,leodemoura/lean,digama0/lean,fpvandoorn/lean,Kha/lean,leodemoura/lean,digama0/lean,Kha/lean,fpvandoorn/lean,fpvandoorn/lean,leanprover/lean,digama0/lean,leanprover/lean,leanprover/lean,fpvandoorn/lean,fpvandoorn/lean,digama0/lean,leodemoura/lean,dselsam/lean,leodemoura/lean,fpvandoorn/lean,dselsam/lean,dselsam/lean,dselsam/lean,digama0/lean,leanprover/lean,leanprover-community/lean,leodemoura/lean