LDV

This is a simplified version of our DagChain system. Specifically,

• All the wallet addresses are maintained by a genesis node (#1 node)
• All the transactions are issued by the genesis node (#1 node), and then are broadcast to the other nodes
• Each time, an address will be selected randomly as the sender, while another address will be selected randomly as the receiver
• To simulate the different views of tips due to the network latency, the tips cited by a transaction will not be deleted from the tip collection immediately. Instead, these tips will be marked by their cited flags and be deleted from the tip collection later, either periodically or by a outer cli command