Renamed realname to name in users table

We do not necessarily need the real name. A nickname would be
sufficient.

db/migrate/20170405144026_rename_user_realname_to_name.rb

@@ -0,0 +1,5 @@
+class RenameUserRealnameToName < ActiveRecord::Migration[5.0]
+  def change
+    rename_column :users, :realname, :name
+  end
+end