Now that the new reordering optimizer has been enabled by default it's 
becoming more important to make it possible to set tolog options 
application-wide. This would allow projects to use the new Ontopia release 
without having to use the new optimizer and without having to turn it off 
in every single query.

The system should look up properties like so:
  * first check for options set in the query itself,
  * then check for options set in tolog.properties (loaded from classpath),
  * finally check for options set in rdbms.properties (if using RDBMS).