Simplify a bit the loop to read our config file

- split the one-liner into a for and an if
- use open() as a context manager
- don't use string.strip which is gone in python3

Signed-off-by: Julien Cristau <jcristau@debian.org>

britney.py

@@ -364,7 +364,12 @@ class Britney(object):
         # are handled as an ad-hoc case
         self.MINDAYS = {}
         self.HINTS = {'command-line': self.HINTS_ALL}
-        for k, v in [map(string.strip,r.split('=', 1)) for r in open(self.options.config) if '=' in r and not r.strip().startswith('#')]:
+        with open(self.options.config) as config:
+            for line in config:
+                if '=' in line and not line.strip().startswith('#'):
+                    k, v = line.split('=', 1)
+                    k = k.strip()
+                    v = v.strip()
                     if k.startswith("MINDAYS_"):
                         self.MINDAYS[k.split("_")[1].lower()] = int(v)
                     elif k.startswith("HINTS_"):