Felix Herrmann authored Feb 15, 2021 and Stefan Busemann committed Feb 15, 2021

* Add Constants.php to store extension constants
* Add Services.yaml
* Update backend module mainModule from `voting` to `web`
* Update deprecated usage of `GeneralUtility::verifyFilenameAgainstDenyPattern` to `GeneralUtility::makeInstance(FileNameValidator::class)->isValid`