Eliminated attackRange variable for Character class.
Eliminated attackRange from Character class

Eliminated attackRange variable from Character class.  Currently
replaced with the range of the characters standard attack action.
Massive Level refactoring and additional AI classes.

The Level class no longer uses a Dictionary of Vector2, Character pairs
to locate the characters.  Each Tile has an occupant variable to keep
track of the Character on the space.  The AI classes give variety to the
types of enemies to play against.
Fixed conflicts with previous commit
Fixed problem with attacking an empty space
Implemented file-generated levels
Generalized Cursor class.  Created another level with multiple player and enemy units.
Added a second level and a way to transfer between levels.
Fixed bug with cursor walking off of level.
Commiting recent changes.  Preparing for merge.
Preparing for merge
Merging #2!