"Ethereum" Keccak

[aerique]

Hi, I'm working on a side project for which I have to generate hashes for Ethereum, which uses the old padding of 1 instead of 6. Changing it on this line fixed it for me:

https://github.com/Egor-Skriptunoff/pure_lua_SHA/blob/master/sha2.lua#L4618

Is there any chance of making this configurable for a user of the module or would you accept a PR for this?

This is so one does not have to maintain one's own fork of this project.

(I use this project because of its speed, easy of use and also because I use LuaJit which a lot of other projects do not support (anymore).)

Reference: https://ethereum.stackexchange.com/questions/30369/difference-between-keccak256-and-sha3