fix integer cast bug

Gotta love Rails.

app/lib/user_settings_decorator.rb

@@ -173,6 +173,8 @@ class UserSettingsDecorator
 
   def integer_cast_setting(key, min = nil, max = nil)
     i = ActiveModel::Type::Integer.new.cast(settings[key])
+    # the cast above doesn't return a number if passed the string "e"
+    i = 0 unless i.is_a? Numeric
     return min if !min.nil? && i < min
     return max if !max.nil? && i > max
     i