(Binary Simulator) Clone detection catches SMT solver exceptions
(Binary Simulator) Improvements to clone detection results

* Added busy-timeouts to the show_results tool so that it can be
  used at the same time the database is being generated.  Previously,
  it had a high probability of aborting if the semantics clone database
  was being generated in parallel at the same time.

* Changed the way file names are presented when listing a function
  whose source code spans multiple files.

* Increased the size of the file index column to keep things
  aligned better.