Update Consensus not to dependent on validator module

[shuse2]

Description

• Move BFT module into consensus
• Update BFT module BFTParameters to store generator/BLS keys as below

{
	prevoteThreshold: bigint;
	precommitThreshold: bigint;
	certificateThreshold: bigint;
	validators: {
		address: Buffer,
		bftWeight: bigint,
		blsKey: Buffer,
		generatorKey: Buffer,
	}[];
	validatorsHash: Buffer;
}

• BFTParameters now can have bft weight 0, and order by shuffled address
• Add API getValidator(address: Buffer, height: number): Validator which returns Validator information for specified height. (it is used to get a generator key to check signature)
• Update generator and consensus not to be dependent on validators module, but use bft module or consensus instead
• Fix impliesMaximalPrevotes

Acceptance Criteria

• Fix all unit tests
• Check dpos example and ensure block execution / generation is working