Added new functions to handle HOL goals and lemmas.
Added a funtion to send types and sorts information to ATP: they are clauses written to a separate file.
Removed several functions definitions, and combined them with those in other files.
Added several new functions that convert HOL Isabelle rules to FOL axiom clauses. The original functions that convert FOL rules to clauses stay with the same names; the new functions have "H" at the end of their names.
Also added function "repeat_RS" to the signature.