This was exactly what I intended to develop myself for my project. I found this completely randomly while surfing through the internet and this maked me so happy. Thank you very much.
Edit: This lacks capasitors and resistors. If you don't want to implement simple physics even a hard-coded clock module(just like "and" and "not" modules) would work. or maybe an option for imputs to work like a clock with adjustable frequancy. Any of these would greatly improve this app.
Edit Edit: I managed to make a clock with xor gates but frequancy is depent on the update rate of simulation so you cant change it.