Uses node.js and HD-mnemonic wallet. You should have a secret.json file with 12-word mnemonic.
Format for secret.json file:
{ "mnemonic": "<12 words of mnemonic>" }
It will be used to create an Ethereum wallet.
Run npm install testnet_ethereum_hdwallet to install this package.
node wallet.js will send an address and private key associated with mnemonic in secret.json.