Fixed some merge issues:

- temporary tables now works
- mysql-system_tables updated to not use temporary tables
- PASSWORD() function fixed
- Support for STATS_AUTO_RECALC, STATS_PERSISTENT and STATS_SAMPLE_PAGES table options

mysql-test/mysql-test-run.pl

@@ -552,7 +552,7 @@ sub main {
     }
   }
 
-  if ( not defined @$completed ) {
+  if ( not @$completed ) {
     mtr_error("Test suite aborted");
   }