Fixed doctest and removed test code.

`oct2py/utils.py`'s doctest can fail depending on the interpreter implementation:

    File "/home/ch/repositories/myoct2py/oct2py/utils.py", line 97, in oct2py.utils.Struct
    Failed example:
        print(a)
    Expected:
        {'c': {'d': 'eggs'}, 'b': 'spam'}
    Got:
        {'b': 'spam', 'c': {'d': 'eggs'}}

See also:  https://docs.python.org/2/library/stdtypes.html#dict.items

> CPython implementation detail: Keys and values are listed in an arbitrary order which is non-random, varies across Python implementations, and depends on the dictionary’s history of insertions and deletions.

pprint sorts by dictionary keys and should fix this problem.