Ensure mirrorlist generator works if no status available

Saw this error come through on the live site today, as well as being
reproducible when no mirror check runs have happened in the last 24 hours on
a development machine. Let mirrors that have no available checks show up on
this page, but be sorted last and show a score of unknown.

Signed-off-by: Dan McGee <dan@archlinux.org>

mirrors/views.py

@@ -11,7 +11,6 @@
 from .utils import get_mirror_statuses, get_mirror_errors
 
 import datetime
-from operator import attrgetter
 
 class MirrorlistForm(forms.Form):
     country = forms.MultipleChoiceField(required=False)
@@ -77,10 +76,14 @@ def find_mirrors(request, countries=None, protocols=None, use_status=False,
         scores = dict([(u.id, u.score) for u in status_info['urls']])
         urls = []
         for u in qset:
-            u.score = scores[u.id]
-            if u.score and u.score < 100.0:
+            u.score = scores.get(u.id, None)
+            # also include mirrors that don't have an up to date score
+            # (as opposed to those that have been set with no score)
+            if (u.id not in scores) or \
+                    (u.score and u.score < 100.0):
                 urls.append(u)
-        urls = sorted(urls, key=attrgetter('score'))
+        # if a url doesn't have a score, treat it as the highest possible
+        urls = sorted(urls, key=lambda x: x.score or 100.0)
         template = 'mirrors/mirrorlist_status.txt'
 
     return direct_to_template(request, template, {