update demo scripts

* add setup to combine init steps, configurable initial mint
  * bash -e -> bash and be explicit about errors with || exit $?
  * feed transaction logs to validator, too

multinode-demo/setup.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+TOKENS=${1:-1000000000}
+
+cargo run --release --bin solana-mint-demo <<<"${TOKENS}" > mint-demo.json
+cargo run --release --bin solana-genesis-demo < mint-demo.json > genesis.log
+
+cargo run --release --bin solana-fullnode-config -- -d > leader.json
+cargo run --release --bin solana-fullnode-config -- -d > validator.json