name-parser: Fix unify_style_names()

[why]
The code is obviously wrong. No effect has been seen, though.

First we check if a certain string is a key in the dict.
If it is, we retrieve the value with the string lower-cased as key.

This does not make sense.

[how]
All the keys are lower case anyhow, so the code seems unneeded. Maybe it
is a leftover. The styles that go into it _and are in the dict_ all come
from a regex-enabled search and thus are lower-cased.

Whatever, to have the correct code we use the lower-cased string for
both, checking for existance and retrieving the value - this is the only
sane approach.
Also change to dict.get() method instead of a self made if code.

Signed-off-by: Fini Jastrow <ulf.fini.jastrow@desy.de>

bin/scripts/name_parser/FontnameTools.py

@@ -71,9 +71,7 @@ class FontnameTools:
             #'semibold':     'Demi',
             'normal':       'Regular',
         }
-        if style_name in known_names:
-            return known_names[style_name.lower()]
-        return style_name
+        return known_names.get(style_name.lower(), style_name)
 
     @staticmethod
     def find_in_dicts(key, dicts):