Compatibility with Nextcloud 14
Same as in gpxedit-oc#43.
Besides that i found out that you use quite long identifier names in your database schema, which will cause issues with oracle support. We added a check for this in 14, but this might cause an error in future versions. To fix that, please make sure you specify supported databases in your apps info.xml (https://nextcloudappstore.readthedocs.io/en/latest/developer.html#info-xml)