Refactored AIDirector: dynamic disaster chances

Disaster chances can now be passed to the constructor, instead
of using final static variables.
Added Sprite for water to Sprite class
Added method to EntityFactory for creating water
Expanded stub for Water class

Class now contains constructor and methods for adding and removing
water.
Added auhor to makeWater() in EntityFactory
Added javadoc to Water class
Changed randomFire() method to use Logger
Added methods for getting corner position of map

Added methods for getting the maximum x and y values and a method for
getting the combined corner position to the World class.
Added flood disaster to AIDirector

-Added randomFlood() method for creating the  flood;
-Added floodChance field and constructor parameter.
AIDirector constructor needs new parameter
Added javadoc to flood disaster methods + fixed bug

isEdgePosition() method did not determine if a position was at the edge
the right way.
Changed visibility of disaster methods to private

Because they are only going to be used locally.
Added code for triggering flooddisaster

Flood is now randomly triggered in randomDisasters() in AIDirector.
Changed way of triggering earthquake in AIDirector

Triggering an earthquake is now consistent with triggering other
disasters, as it is now also using a randomX() mmethod. Also changed
visibility of earthquake method, because it is only used locally.
Encapsulated fps field in World class

This field was public and is now private. Getter and setter
methods are used now. Also, assert statement for the setter has been
added. Existing field references have been converted to getter and
setter calls.
Merge branch 'feature-flood-disaster-minimal'

Conflicts:
	src/server/src/main/java/disastercontrol/AIDirector.java
	src/server/src/main/java/disastercontrol/DisasterControl.java
	src/server/src/main/java/disastercontrol/entity/World.java
	src/server/src/main/java/disastercontrol/processor/FireProcessor.java