Allow quickjump to buildings

[crykn]

Allow quickjumping/teleporting to important buildings.

Deatils

Add an InputListener to GameMapScreen that includes the following keybindings:

1	Teleport to the market
2	Teleport to the townhall

Tasks

• Create key bindings and an InputListener; take a look at GameSpeedInputProcessor for orientation
• Each keypress should teleport the player to the buildings, i.e. set their camera position. So there needs to be a way to calculate the cameras position from the building one's (BuildingSlot#getPosX(), BuildingSlot#getPosY()).