Refactor gameplay into encounters

[jdpdev]

Encounters

When two players face off against each other (pitcher/batter, fielder/runner, etc), it is called an encounter.

Each encounter:

• Contains logic and calculations about how to resolve the encounter
• Opens a UI (perhaps specific to the encounter) to show the player what is happening

When the game detects an encounter happening, it begins an encounter of the specific type to handle the action.

Basic Encounters

• Batter vs pitcher #10 Batting/pitching
• Fielding and gathering ball #11 Fielding the ball, gathering (after a hit)
• Fielder/runner force out #12 Base-fielder vs runner, force out
• Fielder/runner in open #13 Base-fielder vs runner, no force out