Bugfix/113 field UI language

[i-just]

Description

• field’s base config now translates nn language code to no code (CKEditor has no and nb translation files)
• added translations/nn/ckeditor.php file, which is a copy of the nb translations as a starting point
• added functionality that respects cke config language setting and registers corresponding native CKEditor translation files; therefore, it’s now possible to have the app language set to nb but choose to use more complete no language for the CKEditor-provided translations; (it’s now also possible to have 2 cke fields in one entry and have one of them have the UI in, e.g. English and another in, e.g. French)

Related issues

#113

[brandonkelly]

I removed the field config language checks, because that wouldn’t apply to any other CKEditor asset bundles that get registered via plugins. There also wasn’t any point in loading a language file based on $config['language']['content'], as that only defines the language that the content is being produced for.