Clean other caches also, e.g. build cache

[anders-b-jansson]

Description
Not only the image cache occupies storage space. Make it possible to configure cleaning of also the other types of caches. I don't know to what extent the LRU logic can be used for those entities, but some kind of kept together cleaning would be nice.
One alternative would be to set a limit per type, another alternative to set an aggregate limit.

Alternatives considered
Run various docker prune commands on schedule - but why not let docuum handle it all, when it handles image cache cleaning so well?

Additional context
If using docker for not only running but also building, then you may end up in a situation like this:

prompt$  docker system df
TYPE            TOTAL     ACTIVE    SIZE      RECLAIMABLE
Images          150       1         100.9GB   98.32GB (97%)
Containers      1         1         0B        0B
Local Volumes   0         0         0B        0B
Build Cache     3493      0         267.6GB   267.6GB

Here I have an image limit set, which docuum keeps below 100 G, but the build system using this environment overshadows it.

[stepchowfun]

Hi @anders-b-jansson, thank you for filing this feature request! I think Docuum should do this, and I'd be happy to review a PR for it if anyone has time (but please loop me in on the design).

Related: #68, #271

(I might end up closing this or one of the other issues to deduplicate them.)