Hardcoded Bootstrap + Relay Nodes (#2359)

* default bootstrap node and local network flag

* default relay node value

* Update shared/p2p/service.go

Co-Authored-By: rauljordan <raul@prysmaticlabs.com>

* use no discovery

beacon-chain/usage.go

@@ -44,6 +44,7 @@ var appHelpFlagGroups = []flagGroup{
 	{
 		Name: "cmd",
 		Flags: []cli.Flag{
+			cmd.NoDiscovery,
 			cmd.BootstrapNode,
 			cmd.RelayNode,
 			cmd.P2PPort,