[TASK] Demonstrate exclude flag in makeCategorizable

Add "exclude" option to makeCategorizable example.

Resolves: #57086
Releases: 0.6
Change-Id: Ia9acbe2c886bb960ee59e770923823d0a896308e
Reviewed-on: https://review.typo3.org/28535
Reviewed-by: Francois Suter
Tested-by: Francois Suter