Derive clone for several struct

src/state/active_state.rs

@@ -5,6 +5,7 @@ use super::rlp::encode as rlp_encode;
 use super::blake2::{ Blake2s, Digest };
 use super::utils::types::*;
 
+#[derive(Clone)]
 pub struct ActiveState {
     pub height: u64,
     pub randao: Sha256Digest,

src/state/crystallized_state.rs

@@ -6,6 +6,7 @@ use super::rlp::encode as rlp_encode;
 use super::ethereum_types::U256;
 use super::blake2::{ Blake2s, Digest };
 
+#[derive(Clone)]
 pub struct CrystallizedState {
     pub active_validators: Vec<ValidatorRecord>,
     pub queued_validators: Vec<ValidatorRecord>,

src/state/partial_crosslink_record.rs

@@ -3,7 +3,7 @@ use super::utils::types::{ Sha256Digest, Bitfield };
 use super::rlp::{ RlpStream, Encodable };
 use super::bytes::{ BytesMut, BufMut, Buf };
 
-#[derive(Eq)]
+#[derive(Eq, Clone)]
 pub struct PartialCrosslinkRecord {
     pub shard_id: u16,
     pub shard_block_hash: Sha256Digest,

src/state/recent_proposer_record.rs

@@ -1,6 +1,7 @@
 use super::rlp::{ RlpStream, Encodable };
 use super::utils::types::*;
 
+#[derive(Clone)]
 pub struct RecentPropserRecord {
     pub index: u32,     // TODO: make u24
     pub randao_commitment: Sha256Digest,