SQL Standard allows to use EXCEPT ALL and INTERSECT ALL as set operations.
Currently MariaDB Server does not support them.
The goal of this task is to support EXCEPT ALL and INTERSECT ALL
1. at syntax level - allow to use operators EXCEPT ALL and INTERSECT ALL in query expression body
2. at execution level - implement these operations employing temporary tables
(the implementation could use the idea similar to that used for the existing implementation of the INTERSECT operation).