read/check_specification: proper type inference across multiple sections, result is in closed form; added read/check_free_specification for single section, non-closed form;
read/check_specification: proper type inference across multiple sections, result is in closed form;
added read/check_free_specification for single section, non-closed form;

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle