Replace TAB to 4 spaces

[litmon]

When I run python test.py, it has crashed. So I fixed to replace TAB to 4 spaces.

$ python test.py
File "test.py", line 57
    if not os.path.exists('results'): os.mkdir('results')
                                                        ^
TabError: inconsistent use of tabs and spaces in indentation

@Kyubyong