Castle Wall Hazard Map (#101)

* castle_wall map

Wall of hazards around the board with dangerous bridges.

- add support for all standard board sizes
- hazard placement for all board sizes

* passage food placement for all board sizes

* 4 snake starting positions for all maps

* only one food can spawn on a bridge

* support 8 snakes for all board sizes

support 12 snakes on XLarge and XXLarge board sizes

* max 2 food sm/med/lg and max 4 food on xlg/xxlg

no food in the first 10 turns

* sort generated hazard positions

* remove 'uninteresting' castle wall map board sizes

* refactor castle wall map to align with #103

* align map castle wall meta Name with ID

* set MinPlayers to 1 for castle wall map

* pass max snake/food and startPosition to priv func

* fix castle wall food placement and refactor tests

* avoid food spawn by snake heads on castle wall map

- fixes forced food spawning infront of snake issue on large & xlarge maps with double walls