Improve load times by off loading property insertion to a background thread

• In my sample binlog of 40mb. I observed up to 2x speed up. Before 15s. After 7s.
• A 3s is spent in the Analyzing step which remains unchanged. Split the load message this timing messages.
• Parsing the binlog alone takes 5s. The queue backs up when processing ProjectStarted Event, as it parses the Properties and Items.