Some rewording, typos and switching to infinitve

This value was changed recently, and every locale which had it set was using the
same value as the default. This value is still the default in the new location.

* Dutch language files for Ruby code

 * Created RoR translation ymls:
   * config/locales/devise.nl.yml
   * config/locales/doorkeeper.nl.yml
   * config/locales/nl.yml
   * config/locales/simple_form.nl.yml

 * Modified RoR config and helper
   * app/helpers/settings_helper.rb
   * config/application.rb

* Dutch language javascript locale

 * Created javascript locale files:
   * app/assets/javascripts/components/locales/index.jsx
   * app/assets/javascripts/components/locales/nl.jsx

 * Reference the newly created locale files:
   * app/assets/javascripts/components/containers/mastodon.jsx

* Fix syntax error in locale file (nl)

* Fix missing translate in js locale (nl)

* Convert all ruby Dutch locale (nl) file to utf8

Fix yml conversion issues.

* Fix duplicated key in devise.nl.yml

* Fix indentation error in doorkeeper.nl.yml