rewrite collision detection system

changes in Aabb:
rename class Aabb to Hitbox
constructor now accepts any two vectors
add method isNone()
rewrite method collides as:
 - static collides(a,b)
 - collidesWith(b)
rename Hitbox attributes and methods to more intuitive
 - corners are now named min, max
 remove unused Position enum

changes in World:
Player is now initially centered on his home tile
Player center is independent from sprite and hitbox

changes in Entitity:
add getHitbox method to all Entities

changes to Player
rewrite collision detection for Player
 - add detectTileCollisions to choose Tiles for checking
 - add collideWithTile which stops and bumps players backwards
remove unused methods from Player:
 - checkCollisionsWorld
 - isAnyField
 - collisionWithField

bits of reformatting and documentation addet here and there

Game.cpp:
replace checkCollisionsWorld with detectTileCollisions

Menu.cpp:
fix warning on missing brackets

main.cpp:
revert Player texture to Player_White

add libstdc++-6.dll to Release