Remove default enabling of gravatar, check on initial confirmation of e-mail address and on any changes afterward if

a gravatar exists and enable then if the user hasn't uploaded a picture.

db/migrate/20131029121300_set_default_gravatar_to_false_for_privacy.rb

@@ -0,0 +1,9 @@
+class SetDefaultGravatarToFalseForPrivacy < ActiveRecord::Migration
+  def up
+    change_column :users, :image_use_gravatar, :boolean, :default => false
+  end
+
+  def down
+    change_column :users, :image_use_gravatar, :boolean, :default => true
+  end
+end