End line with period

(saves a translation)
Commit dutch translation:

- some english was altered and some duplicates removed:
  - required /database/ tables -> consistency
  - duplicates for "Exception message was"
Consistency and duplicates:

- Removed several duplicates in translation
- Favored "required database tables" over "required tables" in the
  controller and removed the resulting and already present duplicates
Merge pull request #30 from melvyn-sopacua/locale_nl_NL

Locale nl nl