World has a lot of type conversion warnings. Take care of most of them,
for a slight performance hit ( :( ).
Re-order constructor parameters to match declaration.
Move FillColumn to a more appropriate place.
GetBlock gets called a lot : use direct memory access of the vector
rather than going through bounds checks with .at().
Introduce an integer overload to remove warnings.
Player: Add rotation and linear speeds, as well as their current state.
Player: Allow to move in the local coordinates and compute
world-speed equivalent.
Player: Update movement axis while rotating.
World: Add a function to advance a step.
Main: Handle key events, add world step in the main loop.
Implement the basic raycaster, checking every block intersection and the block
linked to that position.
Split the screen uniformally along the width.
Add data needed for camera maths in the Player class
Specify constraints on the raycast parameters.
Render the screen using the raycasts.
Call the renderer in the main loop.
