SPACES_BEFORE_COMMENT column mode violates PEP8 policy of two spaces before comment

Now that #667 is resolved, I have a concern about the behavior: specifying multiple values so as to use column alignment results in inline comments preceded by a single space. Shouldn't there always be two spaces as a minimum regardless of column alignment?

For example, this PEP8 compliant code:

```
else:
class args:
cgi = True # called from cgi
chase = True # Follow freeplane links to other local maps
long_url = False # Use short 'oldid' URLs for mediawikis
urls_online_only = False # Emit urls for @online only
pretty = False # Print as HTML with citation at end
query = None # Query the bibliographies
query_c = None # Query re.compiled
```

loses a space

```
else:

class args:
cgi = True # called from cgi
chase = True # Follow freeplane links to other local maps
long_url = False # Use short 'oldid' URLs for mediawikis
urls_online_only = False # Emit urls for @online only
pretty = False # Print as HTML with citation at end
query = None # Query the bibliographies
query_c = None # Query re.compiled
```