1) Change transaction boundary in autocommit off mode

   per recent discussion in pgsql-odbc. Now SELECT is
   a boundary but VACUUM isn't.
2) Put back the error handling behavior. When elog(ERROR)
   was detected the driver automatically issue "ABORT"
   if a transaction is in progress.
3) Driver version is 7.01.0003(Dave already set it but
   it was put back).