minmod_internal: Inner function of minimal modification of whole Boolean model
In BTR: Training and Analysing Asynchronous Boolean Models

This function generates all possible boolean models minimally modified. Returns a lists of 2 lists, deleted models and added models

1	minmod_internal(bm, index, encoded, model_encoding, and_bool, self_loop = F)

`bm`	S4 BoolModel object.
`index`	integer. Specifying rule of which gene to modify.
`encoded`	logical. Return Boolean models in encoded form to save space.
`model_encoding`	list. Only used if encoded=T.
`and_bool`	logical. Default to check_and() if unspecified.
`self_loop`	logical. Whether to allow self_loop in random starting model. Default to F.