Activated TTL cache by default

Makes sense now since we don't have etag any more and purge is now OK from legacy scripts using
php ezpublish/console ezpublish:legacy:script bin/php/ezcache.php --clear-all
Changed: added additional timezones to use during travis tests
Fixed EZP-20859 Twig exception trying to generate path to legacy module with no views
Fix EZP-20867: Error when creating Image fieldtype without validator configuration

https://jira.ez.no/browse/EZP-20867

Similar approach used in: https://github.com/ezsystems/ezpublish-kernel/blob/master/eZ/Publish/Core/FieldType/TextLine/Type.php#L48
Fixed: Unit tests skipped because of unknown sequences

Partially reverts 933ad091aaadd1109ed60deb0dba77b07c917206
Changed: Uniformize fixture schema file to easily compare them

Fixing many schema differences while doing this.
Implemented EZP-20851: Setup Travis tests to also test prostgres for ezpublish-kernel & -legacy