Strip out old code

All of these files have been moved to either:

- https://github.com/sigp/lighthouse-beacon
- https://github.com/sigp/lighthouse-validator
- https://github.com/sigp/lighthouse-common

For rationale, see: https://github.com/sigp/lighthouse/issues/197

validator_client/src/duties/traits.rs

@@ -1,20 +0,0 @@
-use super::EpochDuties;
-use bls::PublicKey;
-use types::Epoch;
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum BeaconNodeError {
-    RemoteFailure(String),
-}
-
-/// Defines the methods required to obtain a validators shuffling from a Beacon Node.
-pub trait BeaconNode: Send + Sync {
-    /// Get the shuffling for the given epoch and public key.
-    ///
-    /// Returns Ok(None) if the public key is unknown, or the shuffling for that epoch is unknown.
-    fn request_shuffling(
-        &self,
-        epoch: Epoch,
-        public_key: &PublicKey,
-    ) -> Result<Option<EpochDuties>, BeaconNodeError>;
-}