software/fluentd: Finalize instance parameter form
Add the missing files needed to be able to directly input a fluentd configuration in panel.rapid.space's parameter form, instead of having to painstakingly input an escaped version of it through the Raw XML field.
In the future, additional software types can be defined to restrict the parameter inputs in some specific use cases (for example the forwarding of ORS logs to a Wendelin instance).
Finally, the Wendelin tutorial web pages related to the setup of fluentd will need to be updated accordingly, which I will take care of.