fix issue with utf8 encoding in logger stdout

this fixes a bug with the logger and utf8:

```
UnicodeEncodeError: 'ascii' codec can't encode character u'\u2713'   ordinal not in range(128)
```

heres a link to docs referencing `utf-8` instead of `utf8`: 

https://docs.python.org/2/howto/unicode.html#the-unicode-type