support ensemble config templates

[vanhauser-thc]

Not sure how this could look but: the issue is that we use ziggy on very special targets, hence our default setup is not ideal for other targets, e.g. text input based ones. Therefore it would be great if we had e.g. 4 different setups, e.g. "binary", "text", "generic" and "blockchain", and these set specific parameters for AFL++ and libafl. e.g I added scale encoding for AFL++ now, but when not fuzzing substrate based blockchains this is nonsense to active. also text input targets would run more effective with a different setup than binary input targets.