Add rubocop spacing rules

We were following these rules in most places; we just didn't define them
anywhere.

lib/score_calculator.rb

@@ -6,7 +6,7 @@ module ScoreCalculator
     period = [1, [max_period, resource_age(resource)].min].max
 
     votes_total = resource.votes_for.where("created_at >= ?", period.days.ago).count
-    votes_up  = resource.get_upvotes.where("created_at >= ?", period.days.ago).count
+    votes_up = resource.get_upvotes.where("created_at >= ?", period.days.ago).count
     votes_down  = votes_total - votes_up
     votes_score = votes_up - votes_down