- add new methods to DBTools for manipulating primary keys
- updated schema: remove auto-inc column from test_result_bugs and make compound primary key
- update populatedb.pl to update test_result_bugs table on existing installs
git-svn-id: svn://10.0.0.236/trunk@227585 18797224-902f-48f8-a5cc-f745e15eee43