Adjust cache name to match TYPO3 v10 convention without "cache_" prefix.
Add default configuration to prevent issue if integrator does not
configure cache.
Allow editors to select specific events to display.
Therefore add new necessary demand and setting for events and respect
them within repository.
Relates: #8092
The icon is still a placeholder.
Still we provide the identifier to already use it in sitepackages.
That way the extension can exchange the file, but foreign configuration
can stay.
Relates: #8092