Add describe() methods to all of the classes in the sandbox

[wsowens]

Our sandbox is composed of entities, items, characters, and locations.
Each of these classes needs a flexible, describe() method.

For reference, we have agreed upon the following convention:

class Foo:
    _name               # private variable holding the name

    def __repr__(self): # returns a proper, pythonic representation

    def __str__(self):  # returns the name

    def describe(self, *args):     # returns the a thorough description of the thing

info() should allow for some structured input and return appropriate output.
For example, given Wizard bill:

>>> bill.info("wielding")
"wielding an enchanted staff"
>>> bill.info("epithet")
"the Wizard"
>>> bill.info("epithet", "wielding")
("the Wizard", "wielding an enchanted staff")

This isn't set in stone, so other ideas are definitely welcome.

We can probably implement this by having some kind of dictionary.