Bug fixes

Resolve pareview issues.

This is just a fixup of 7.x-2.3.

* Fixing issue where user with 'edit all languages' was unable to edit a language
* Issue #3021454 by railgun, nterbogt: Translation operation links appear regardless languages allowed for moderation

Add hook_install() and hook_requirements().
Hook support completed.
Small refactoring and fixes.

Fix #3010791: LIne 56 of webform_steps.module gives Warning.

Bug fixes:
#3040522: Error: Call to a member function bundle() on null in Drupal\mixitup_views\MixitupFunc->populateFilters() (line 121 of ...modules/contrib/mixitup_views/src/MixitupFunc.php)