priv_key.go
func GenPrivKeySecp256k1() PrivKeySecp256k1 {
	privKeyBytes := [32]byte{}
	copy(privKeyBytes[:], CRandBytes(32))
	priv, _ := secp256k1.PrivKeyFromBytes(secp256k1.S256(), privKeyBytes[:])
	copy(privKeyBytes[:], priv.Serialize())
	return PrivKeySecp256k1(privKeyBytes)
}
func GenPrivKeySecp256k1() PrivKeySecp256k1 {
	privKeyBytes := [32]byte{}
	copy(privKeyBytes[:], CRandBytes(32))
	priv, _ := secp256k1.PrivKeyFromBytes(secp256k1.S256(), privKeyBytes[:])
	copy(privKeyBytes[:], priv.Serialize())
	return PrivKeySecp256k1(privKeyBytes)
}
/*
// Deterministically generates new priv-key bytes from key.
func (key PrivKeySecp256k1) Generate(index int) PrivKeySecp256k1 {
	newBytes := cdc.BinarySha256(struct {
		PrivKey [64]byte
		Index   int
	}{key, index})
	var newKey [64]byte
	copy(newKey[:], newBytes)
	return PrivKeySecp256k1(newKey)
}
*/