Fixed creature creation in Assets

Change the string to the enum
Added list of animation to CreatureRepresentation

Added a list to CreatureRepresentation so that it is possible to queue
up animations on it.
Small fixes and states in BattleScreen

Small fixes includes changing the representation where the mouse hovers
from a Vector2 to a Position and removing/renaming some variables.
The states keeps track of what is supposed to happen at the
moment(animate, wait for input etc.)
Added states to CreatureRepresentation

Added states to CreatureRepresentation to keep track of what it is
supposed to do(Normal, Moving, Dead)