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

eth2/attester/src/test_utils/mod.rs

@@ -1,7 +0,0 @@
-mod epoch_map;
-mod local_signer;
-mod simulated_beacon_node;
-
-pub use self::epoch_map::EpochMap;
-pub use self::local_signer::LocalSigner;
-pub use self::simulated_beacon_node::SimulatedBeaconNode;