3-3: Create genesis.json

If you start pocket for the first time using the --mainnet flag, a genesis.json file will be created. The other option is to do the following:

1. Change to the .pocket/config directory:

   cd ~/.pocket/config
2. Use the following command to get the genesis.json file:

   wget https://raw.githubusercontent.com/pokt-network/pocket-network-genesis/master/mainnet/genesis.json genesis.json