Create a local testnet (#2614)

The testnet will be on the local computer and have 1 eth1 node,
4 beacon nodes, 1 validator with 20 vc's.

scripts/local_testnet/kill_processes.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+# Kill processes
+
+# First parameter is the file with
+# one pid per line.
+if [ -f "$1" ]; then
+  while read pid
+    do
+      echo killing $pid
+      kill $pid
+    done < $1
+fi
+
+