(Binary Clone Detection) Optimized queries

Now takes minutes instead of hours.
(Binary Simulator) Fixe bug in SQL query for clone detection

* The syntactic_clone_pairs table listed pairs without ensuring
  that the first function ID of the pair is smaller than the second.
  This ordering is used by all other pair-similarity tables. A
  similarity relationship between two functions is symmetric and
  reflexive, so there's no reason to store redundant or trivial
  pairs.