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

beacon_node/beacon_chain/src/checkpoint.rs

@@ -1,43 +0,0 @@
-use serde_derive::Serialize;
-use types::{BeaconBlock, BeaconState, Hash256};
-
-/// Represents some block and it's associated state. Generally, this will be used for tracking the
-/// head, justified head and finalized head.
-#[derive(PartialEq, Clone, Serialize)]
-pub struct CheckPoint {
-    pub beacon_block: BeaconBlock,
-    pub beacon_block_root: Hash256,
-    pub beacon_state: BeaconState,
-    pub beacon_state_root: Hash256,
-}
-
-impl CheckPoint {
-    /// Create a new checkpoint.
-    pub fn new(
-        beacon_block: BeaconBlock,
-        beacon_block_root: Hash256,
-        beacon_state: BeaconState,
-        beacon_state_root: Hash256,
-    ) -> Self {
-        Self {
-            beacon_block,
-            beacon_block_root,
-            beacon_state,
-            beacon_state_root,
-        }
-    }
-
-    /// Update all fields of the checkpoint.
-    pub fn update(
-        &mut self,
-        beacon_block: BeaconBlock,
-        beacon_block_root: Hash256,
-        beacon_state: BeaconState,
-        beacon_state_root: Hash256,
-    ) {
-        self.beacon_block = beacon_block;
-        self.beacon_block_root = beacon_block_root;
-        self.beacon_state = beacon_state;
-        self.beacon_state_root = beacon_state_root;
-    }
-}