Implemented various optimisations of the 0.2.0 version, including different filtering and rewriting approaches for model enumerations
* ADD prefilter for stable model computation (hybrid and naive)
* ADD implementation with one big rewritten formula instead of many
* ADD second version of bdd rewriting method
* FIX documentation, UPD flake
* UPD Readme, usage
* ADD hybrid options for grounded and transformation
