* Add PHP and Symfony framework requirements to manifest.json
* Refactor manifest.json to remove PHP and Symfony framework requirements
* Remove Symfony version requirements from manifest.json
* Add recipe version 4.0 for outcomer/symfony-json-schema-validation
Adds auto_cast_query and auto_cast_path options to the default
outcomer_validation.yaml config, matching the bundle's 4.0 release.
* Use the new schemas (path/domain pairs) option in the 4.0 recipe
schemas_path/schema_domain are deprecated in favor of schemas as of
bundle 4.0.
* Fix YAML indentation to be a multiple of 4 spaces
The CI lint requires every indentation level to be a multiple of 4
spaces; the list item's inline "path:" key broke that rule.
