adding a finer hierarchy for the items

new file:   src/item/accessory/Accessory.java
new file:   src/item/motionGear/MotionGear.java
new file:   src/item/shield/Shield.java
modified:   src/item/weapon/LaserRifle.java
	LaserRifle inherit from PrimaryWeapon rather than Weapon
new file:   src/item/weapon/PrimaryWeapon.java
new file:   src/item/weapon/SecondaryWeapon.java
Merge branch 'master' into items