Added default upgrade path.
All weapons begin on the normal upgrade path. Subclass may overwrite.
Add shortsword.

Include shortsword weapon.
Add javadoc.

Document setBaseStats() to remind subclasses what needs to be
implemented to fulfill post condition.
Correct misspelling.

Corrected name of method to setCriticalDamage from setCritcalDamage.
Update fields and other references to reflect change.
Move methods to super class.

Refactor methods setPath and setModifier to Weapon super class. These
are universal statuses across all weapons. Exceptions apply to specific
weapons and should be reflected at construction.