Remove jackson hard dependency

This PR is about removing the jackson hard dependency for the Json Encoding operation. Is intended to make it easier to integrate with each project preferences. Briefly, it will query the classloader which Json Mapper is available.

Also, it will allow the user to specify it by configuration.

    new JtwigViewResolver().configuration().render().jsonMapper(<implementation>)

or

    new JtwiConfiguration().render().jsonMapper(<implementation>)

As part of this did some tidy up on the project structure by removing the crazy jtwig-types module.