MariaDB 10.4 upgrade documentation is incomplete

The MariaDB 10.4 upgrade documentation page is currently incomplete.

https://mariadb.com/kb/en/library/upgrading-from-mariadb-103-to-mariadb-104/

The following sections have not yet been populated:

• Incompatible Changes Between 10.3 and 10.4
• Major New Features To Consider

To see an example of what kind of content would be appropriate for these sections, see the upgrade pages for 10.1, 10.2, and 10.3:

https://mariadb.com/kb/en/library/upgrading-from-mariadb-100-to-mariadb-101/

https://mariadb.com/kb/en/library/upgrading-from-mariadb-101-to-mariadb-102/

https://mariadb.com/kb/en/library/upgrading-from-mariadb-102-to-mariadb-103/