Fix minor issue with the pylint Step:

 - indentation issue
 - don't write pylint additional log on a single line

Note: 
I add to overide this class in order to set:
```
 _parseable_line_re = re.compile(
        r'[^:]+:\d+: \[%s(\d{4})?\(.+\), .*\] .+' % _msgtypes_re_str)
```

by default, the pylint step fails to parse the output generated with pylint 1.1.0 configured with:
```
msg-template={path}:{line}: [{msg_id}({symbol}), {obj}] {msg}
```
I think this is equivalent to --output parseable (but I 'm not sure).