Introduce Kate-commitment modification used in Sonic proof system

[nkaskov]

Implement the commitment scheme used in Sonic Proof system together with the tests (it means you need to find an implementation and generate tests). It is described in section 6.2 of proof system spec.

Is has to be compatible with the commitment scheme trait .

Commitments schemes are placed in a directory of zk repository .

As a full example of already implemented commitment scheme LPC commitment can be used.