Add the Chunker trait and move the current Chunker to ChunkerImpl to
implement the trait instead. This allows to use different chunker
implementations by dynamic dispatch and is in preparation for
implementing a dedicated payload chunker.
Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
These aren't installed and are only used for manual testing,
so there's no reason to force them to be built all the time.
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
