Deal gracefully with recommendations of hidden proposals

We were seeing an exceptions in the home page when displaying
recommendations. This was due to trying to load tags of hidden proposals

With this commit we are skipping proposals that that have been hidden,
which will hopefully solve this exception

app/models/user.rb

@@ -328,7 +328,8 @@ class User < ActiveRecord::Base
   end
 
   def interests
-    follows.map{|follow| follow.followable.tags.map(&:name)}.flatten.compact.uniq
+    followables = follows.map(&:followable)
+    followables.compact.map { |followable| followable.tags.map(&:name) }.flatten.compact.uniq
   end
 
   private