Updated medieval tower positions

The melee and ranged towers provide a buffer between enemy spawn points
and the king.
Fixed enemy units not arming themselves

Increased the arming radius of towers so it's easier for peasants to arm
themselves.
Updated troop level text locations

Forgot to move them when the control panel was changed.
Re added squad presets for AI

Allows varied enemy squads to be created.
Created testing scene

Used to test new changes
Removed requirement for number of waves in AI

The number of waves keeps on changing during the testing and balancing
process. Setting a max value of 20 waves that can later be modified
means I don't have to change the number of waves if I want to balance a
scene.
Multiple enemy types initial commit
Fixed missing enemy animations
Squad isn't considered idle until the squad leader is idle