some messy refactoring

- added "True Deteective" splash screen
- added debug message function to display on game screen (no leak)
- fixed a significant leak in level regeneration because of monster path
object being wrongly deleted, now it's fixed with a range for C++11
- bigger refactoring by creating a game-state with some globals, and
moving some monster/player object definitions in their files
- liventities.h has Game class forward declared, or wouldn't compile
because one header includes the other