removed debugging code
fixed QuerySpecification to produce SQL that does UNION or INTERSECT set operations for query group combinations
completed work on creating structured query prototype in DBQuery and QuerySpecification classes
continued work on structured query. Now QuerySpecification generates SQL for a given xml input, and DBQuery uses that SQL to send the query to the db
continued work on structured query -- now it reads the queryspec xml docuemnt and can digest its contents
continued work on developing structured query functionality using the QuerySpecification class -- incomplete still
added incomplete classes for structured query