Implement basic Strategist Singleton

[krogenth]

We'll need to analyze the state of the game, and attempt to estimate the best possible course to win. For now, we will only choose an initial Build Order based on Map size from #4 to initialize a starting building queue. The Strategist should check what the first order is on each frame to see if the requirements(and resources) are available to make the order. Like the Map in #2, this will be a Singleton. For now, we will use queues to store Build Orders for Units to ask for.

The Strategist should contain:

• the amount of minerals spent(including Worker/Building issued orders)
• the total amount of supply(including Overlords in Build Order queue)
• at least a Zerg_Larva, Zerg_Drone, and Zerg_Hatchery Build Order queues

Remember, there may be nothing in the Build Order queue for the Unit asking, it's recommended to use std::optional for this.