Test: correct amount of dots/energizers in start_food

And fixed start_food
Default mode allows playing as pacman with awkward movement
Added --show-pacman-nodes, --show-ghost-nodes
Added specification note about cornering
Removed unused skins
Made background entirely black
Classic pacman sprite
Removed unused boot sprite
Replaced dot and energizer by classic sprite
Draw classic map

Set TILE_SIZE to 24 as multiples of 8px work better with current sprites
TILE_SIZE now const instead of #define
Removed mapEl, objEl left overs
Map is now single sprite
Ghosts now have classic sprites
Don't draw baddie_eyes.png
Removed GUI display delay
Refactor: Removed unused argument
Refactor: walls now bool[]
Fix: not all pacman intersections had cornering
Fix: didn't eat food in corners

This was because we hadn't implemented the recently added cornering
special case (if in wall tile -> pretend to be in nearest intersection)
Refactor: Adjusted comments