fix issue of not being able to exit gb when

a disk read retry is taking forever.

Msg3.cpp

@@ -782,6 +782,11 @@ bool Msg3::doneScanning ( ) {
 		}
 	}
 
+	// if shutting down gb then limit to 20 so we can shutdown because
+	// it can't shutdown until all threads are out of the queue i think
+	if ( g_process.m_isShuttingDown && max < 0 )
+		max = 0;
+
 	// get base, returns NULL and sets g_errno to ENOCOLLREC on error
 	RdbBase *base; if (!(base=getRdbBase(m_rdbId,m_collnum))) return true;