Add Character class

[gcallah]

Class needs at least these methods:

• __init__(name, char_type, init_location) : creates character from character_type dictionary.
• get_name() : e.g., 'Thor'
• pick_up() : e.g., thor.pick_up('hammer'), 'hammer' gets added to list of objects
• move() : e.g., thor.move(some_node), must set self.location = some_node