Merge remote-tracking branch 'kunstmaan/5.0' into fix-slack-channel-link

* kunstmaan/5.0:
  [AdminBundle] Fix icons CKeditor (Kunstmaan#2174)
  fix gulp dependency (Kunstmaan#2172)
  null config for older branches (Kunstmaan#2151)
  remove unnecessary roles on dom nodes (Kunstmaan#2170)
  [NodeBundle] fix issue finding disctinct classes for deleted files (Kunstmaan#2148)
  Translate pagepart type name in delete modal (Kunstmaan#2160)
  [TranslatorBundle] fix non-unique locales in configurator (Kunstmaan#2156)
  [AdminListBundle] use datepicker for DateTimeType filters (Kunstmaan#2159)
  [Docs] Fix the links in the github contributing.md file (Kunstmaan#2166)
  Remove duplicate set in template (Kunstmaan#2168)
  Fixed issue where a date (and time) in the past could be selected when publishing later (Kunstmaan#2163)
  Improved error shown when a page does not have a view location (Kunstmaan#2162)
  [AdminListBundle] Feature/sortable adminlist (Kunstmaan#2143)
  [AdminBundle] revert ckeditor to original version - manual clone - no npm version available (Kunstmaan#2134)
  [NodeBundle] Revert "Fix bug in NodeChoiceType (Kunstmaan#2115)" (Kunstmaan#2133)