Initial beacon node setup.

- Add network crate.
- Add sync crate.
- Add version crate.
- Add lighthouse configuration.
- Add network configuration.

eth2/fork_choice/src/lib.rs

@@ -94,6 +94,7 @@ impl From<BeaconBlockAtSlotError> for ForkChoiceError {
 }
 
 /// Fork choice options that are currently implemented.
+#[derive(Debug, Clone)]
 pub enum ForkChoiceAlgorithm {
     /// Chooses the longest chain becomes the head. Not for production.
     LongestChain,