LEO-II v1.9.5 -- what is new

v1.9.4 plus three repairs, no change to what the prover proves:
* no longer waits forever for a first-order prover that never answers
  (the call now has a deadline of its own);
* --proofoutput 2 reports a missing epclextract instead of running an
  empty command;
* two costs in the term index removed (bound-variable names rebuilt on every
  retrieval, subterm positions hashed three times).