Add camera zoom and pan controls

[wchaney98]

I thought the intention of the ticket was to adjust the camera rather than the actual game window, so I went with that.

Spent way too long getting the camera pan "velocity" to work decently, but was fun to get working.

• Added script to Camera in planet_level.tscn with zoom/pan functionality
• Adjusted same Camera to use "Position Smoothing" - can also easily be turned off
• Input mappings for zoom/pan in Project Settings: middle mouse scroll to zoom, middle mouse press to pan
• Press F to re-center the player
• Default window mode to windowed, just easier to debug, but can adjust if we want to keep fullscreen default

[wchaney98]

This works great! Can you add controller options for this too? I'm thinking pan with right stick, re-center by pushing in right stick or something

Tried implementing that. Also did it so holding L2 + right stick up/down zooms the camera in/out as well