Split common crates out into their own repos (#3890)

## Proposed Changes

Split out several crates which now exist in separate repos under `sigp`.

- [`ssz` and `ssz_derive`](https://github.com/sigp/ethereum_ssz)
- [`tree_hash` and `tree_hash_derive`](https://github.com/sigp/tree_hash)
- [`ethereum_hashing`](https://github.com/sigp/ethereum_hashing)
- [`ethereum_serde_utils`](https://github.com/sigp/ethereum_serde_utils)
- [`ssz_types`](https://github.com/sigp/ssz_types)

For the published crates see: https://crates.io/teams/github:sigp:crates-io?sort=recent-updates.

## Additional Info

- [x] Need to work out how to handle versioning. I was hoping to do 1.0 versions of several crates, but if they depend on `ethereum-types 0.x` that is not going to work. EDIT: decided to go with 0.5.x versions.
- [x] Need to port several changes from `tree-states`, `capella`, `eip4844` branches to the external repos.

beacon_node/beacon_chain/Cargo.toml

@@ -30,12 +30,12 @@ serde_derive = "1.0.116"
 slog = { version = "2.5.2", features = ["max_level_trace"] }
 sloggers = { version = "2.1.1", features = ["json"] }
 slot_clock = { path = "../../common/slot_clock" }
-eth2_hashing = "0.3.0"
-eth2_ssz = "0.4.1"
-eth2_ssz_types = "0.2.2"
-eth2_ssz_derive = "0.3.1"
+ethereum_hashing = "1.0.0-beta.2"
+ethereum_ssz = "0.5.0"
+ssz_types = "0.5.0"
+ethereum_ssz_derive = "0.5.0"
 state_processing = { path = "../../consensus/state_processing" }
-tree_hash = "0.4.1"
+tree_hash = "0.5.0"
 types = { path = "../../consensus/types" }
 tokio = "1.14.0"
 tokio-stream = "0.1.3"

beacon_node/beacon_chain/src/builder.rs

@@ -999,7 +999,7 @@ fn descriptive_db_error(item: &str, error: &StoreError) -> String {
 mod test {
     use super::*;
     use crate::validator_monitor::DEFAULT_INDIVIDUAL_TRACKING_THRESHOLD;
-    use eth2_hashing::hash;
+    use ethereum_hashing::hash;
     use genesis::{
         generate_deterministic_keypairs, interop_genesis_state, DEFAULT_ETH1_BLOCK_HASH,
     };

beacon_node/beacon_chain/src/eth1_chain.rs

@@ -1,7 +1,7 @@
 use crate::metrics;
 use eth1::{Config as Eth1Config, Eth1Block, Service as HttpService};
 use eth2::lighthouse::Eth1SyncStatusData;
-use eth2_hashing::hash;
+use ethereum_hashing::hash;
 use int_to_bytes::int_to_bytes32;
 use slog::{debug, error, trace, Logger};
 use ssz::{Decode, Encode};