fixes #2536 - loading locale .mo files in production mode

- initializer script fixed to look for *.mo files
- Makefile updated to place *.mo into /locale/*/LC_MESSAGES
  (rake gettext:pack places them there as well)
- *.mo files added to foreman.spec
fixes #2542 - sort image listing with datatables
Fixes #2519 - Protect locale changes from validation failure so that
password validation can be run