All code in the bundle is still relying on the transformMarkdown method in
parsers, not on the transform method.
Normal parsers are still working because they still have the method, and
PHP does not have strict type checking for typehints.
However, the SundownParser was still broken. #51 renamed the method to
avoid a fatal error for the interface, but then the method used by the
bundle became missing.
Since flydev has marked his version as deprecated (it was a simple composer port of Michel Fortin's initial project), it seems good to revert the dependency to the stable/continued project.
Refactored way how parsers are initialized, and allow to select parser while rendering
Interface `MarkdownParserInterface` method name was changed from `#transform($text)` to `#transformMarkdown($text)`
