chore(.gitignore): update
chore(.gitignore): update

leanprover/tutorial,avigad/tutorial,leanprover/tutorial,soonhokong/lean-tutorial,leanprover/tutorial,cjmazey/fork_leanprover_tutorial,fpvandoorn/tutorial,Hodapp87/cs6460_project,avigad/tutorial,fpvandoorn/tutorial,cjmazey/fork_leanprover_tutorial,soonhokong/lean-tutorial,cjmazey/fork_leanprover_tutorial,fpvandoorn/tutorial,Hodapp87/cs6460_project,avigad/tutorial,soonhokong/lean-tutorial,Hodapp87/cs6460_project