Move Mobile back into the core.

Add some framework for entity behaviours.
Fix broken formatting from working on laptop.
Fix for only one mobile being placed on the map

The callback for mobile was changing the player start position, and
the single call for the player placement was adding a test monster.
Tidy up code block in DungeonGenerator
Revert back to a 80x25 console for now.

There needs to be some edits elsewhere before we can fully support
othe resolutions.
Add simple framework for combat, needs expansion