Add whiteblock script, CLI options to support it

scripts/whiteblock_start.sh

@@ -0,0 +1,96 @@
+#!/bin/bash
+
+<<COMMENT
+	Used by Whiteblock for simulated network testing.
+
+	Based upon:
+	https://github.com/whiteblock/dockerfiles/blob/a31b412d32d0384de12aa8392e43bac32837b6bc/ethereum/interop-example/launch/start.sh
+
+	Here's an example script used for testing:
+
+	./whiteblock_start.sh \
+		--identity=55c7fc76505ddeb6cf750b1f9f43d6d12c1a53b77ada018a390d7592a7f36dbck \
+		--peers=/ip4/192.168.0.1/tcp/9000 \
+		--validator-keys=/tmp/keygen_10_validators.yaml \
+		--gen-state=/tmp/genesis.ssz \
+		--port=9008
+
+	The example script was run in the target/release directory of lighthouse.
+	The following change was made to this script:
+
+		YAML_KEY_FILE="/tmp/keygen_10_validators.yaml"
+COMMENT
+
+# Flags
+IDENTITY=""
+PEERS=""
+YAML_KEY_FILE="/tmp/keygen_10_validators.yaml"
+GEN_STATE=""
+PORT="8000"
+
+# Constants
+BEACON_LOG_FILE="/tmp/beacon.log"
+VALIDATOR_LOG_FILE="/tmp/validator.log"
+
+usage() {
+    echo "--identity=<hex prepresentation of the priv key for libp2p>"
+    echo "--peers=<peer>"
+    echo "--validator-keys=<path to /launch/keys.yaml>"
+    echo "--gen-state=<path to /launch/state.ssz>"
+    echo "--port=<port>"
+}
+
+while [ "$1" != "" ];
+do
+    PARAM=`echo $1 | awk -F= '{print $1}'`
+    VALUE=`echo $1 | sed 's/^[^=]*=//g'`
+
+    case $PARAM in
+        --identity)
+            IDENTITY=$VALUE
+            ;;
+        --peers)
+            PEERS+=",$VALUE"
+            ;;
+        --validator-keys)
+            VALIDATOR_KEYS=$VALUE
+            ;;
+        --gen-state)
+            GEN_STATE=$VALUE
+            ;;
+        --port)
+            PORT=$VALUE
+            ;;
+        --help)
+            usage
+            exit
+            ;;
+        *)
+            echo "ERROR: unknown parameter \"$PARAM\""
+            usage
+            exit 1
+            ;;
+    esac
+    shift
+done
+
+./beacon_node \
+	--p2p-priv-key $IDENTITY \
+	--logfile $BEACON_LOG_FILE \
+	--libp2p-addresses $PEERS \
+	--port $PORT \
+	testnet \
+	--force \
+	file \
+	ssz \
+	$GEN_STATE \
+	& \
+
+./validator_client \
+	--logfile $VALIDATOR_LOG_FILE \
+	testnet \
+	--bootstrap \
+	interop-yaml \
+	$YAML_KEY_FILE \
+
+trap 'trap - SIGTERM && kill 0' SIGINT SIGTERM EXIT