Tell Git to ignore  file
Update to Rails 4.0.2
Adopt new locale validation behavior

Adopt new default locale validation behavior. Doing so also silences
this deprecation warning:

http://stackoverflow.com/questions/20361428/rails-i18n-validation-deprecation-warning
Merge branch 'rails-4-0-2'

Merge changes related to Rails 4.0.2 update.