When running cli tasks and there's an exception/error - it's helpful to have detailed information displayed

We don't always get enough information when an exception happens to track down where the issue is.
It would be helpful if the tablename and/or the SQL statement was also displayed to help track down problems.

When trying to load a fixture file I was receiving the following:
[Doctrine_Connection_Mysql_Exception]
SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'created_at' cannot be null

As you can see - it doesn't help much as it doesn't display the table/class that's the created_at column is on.

As quick fix - I modified the rethrowException method in Doctrine_Connection to include some information from the invoker (not a great fix - I should really dig deeper and see if there's a __toString() method on classes that can be passed as the invoker):

    /**
     * rethrowException
     *
     * @throws Doctrine_Connection_Exception
     */
    public function rethrowException(Exception $e, $invoker)
    {
        $event = new Doctrine_Event($this, Doctrine_Event::CONN_ERROR);

        $this->getListener()->preError($event);
        
        $name = 'Doctrine_Connection_' . $this->driverName . '_Exception';
        
        $exc  = new $name($e->getMessage() . "\n" . $invoker->getQuery(), (int) $e->getCode());
        if ( ! isset($e->errorInfo) || ! is_array($e->errorInfo)) {
            $e->errorInfo = array(null, null, null, null);
        }
        $exc->processErrorInfo($e->errorInfo);

         if ($this->getAttribute(Doctrine_Core::ATTR_THROW_EXCEPTIONS)) {
            throw $exc;
        }
        
        $this->getListener()->postError($event);
    }