Fix wrong code in ext_localconf.php and ext_tables.php.

See merge request riconet-public/typo3/rico_fairs!11

Add support for TYPO3 8.7.

See merge request riconet/typo3/extensions/rico_fairs!4

* Add composer support.
* Add test and CI support.
* Fix some file content issues.
* Add plugin utility.
* Move some methods calls from ext_localconf.php and ext_tables.php
  to their respective place.

Fix CategoryRepository::findByParent.

See merge request riconet/rico_fairs!2

Fix some bugs with appointments.

Sort by sorting in list view.

Change link in OptIn Eid.

Add empty fair handling in showAction to default-TYPO3 404 handler

Fix some bugs.
Add new icons.
Fix some more bugs.

Update FairRepository.php

See merge request !1

Changed category constraint to logicalOr and contains instead of in, because the query treid to find categories.uid, where the count of related categories is saved, not the uid itself.

Updates setOriginalResource to be compatible with TYPO3\CMS\Extbase\Domain\Model\FileReference::setOriginalResource

Increase the version.

Increase the version.
Mark extension as stable.

Fix some email bugs.