Preserve objects identity

While Pythoscope keeps track of objects and methods called on them it doesn't track the way they are passed around. Because of that it doesn't preserve their identity and can't even reconstruct them properly in other objects' tests.

For example, a code like that:

class Something(object):
    pass
def compare(x, y):
    return x is y
obj = Something()
compare(obj, obj)

would generate a bogus test case, by constructing each argument to compare() separately.