Add support for Zilliqa mining, dualmining and staking

[oliverw]

Discussed in https://github.com/oliverw/miningcore/discussions/1171

^{Originally posted by ei8ht187 February 20, 2022} Many Miners offers the possibility to dualmine Ethereum and Zilliqa. Beside mining, Zilliqa also uses PoS. Therefore, it be great when Miningcore supports this features too.

As far as I understood the Zilliqa documentation, the miningpart is based on ethash. Probably, this would be easy to implement :).