doc(README.md): add 'Auto-reload HTML page' section
doc(README.md): add 'Auto-reload HTML page' section

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