Added Simple Weapons
Added attack bonus to Weapon class
Added Weapon#GetDamageRoll and Weapon#GetCriticalDamageRoll
Also added Attribute class that contains a static method GetAbilityMod
Made Armor concrete and added implementation details.
Updated UML
Added extra integrety checks to Weapon's Setters.
Removed unneeded variable from Weapon#SetThreatRange
Merge branch 'master' into Armor

Conflicts:
	CSCD454-FinalProject/Attributes.cs
	CSCD454-FinalProject/Weapon.cs
Merge branch 'Armor'