dom0/dom0-update: clean up metadata caches after downloading updates (#558)
dom0/dom0-update: clean up metadata caches after downloading updates (#558)

woju/qubes-core-admin,marmarek/qubes-core-admin,QubesOS/qubes-core-admin,QubesOS/qubes-core-admin,QubesOS/qubes-core-admin,marmarek/qubes-core-admin,woju/qubes-core-admin,woju/qubes-core-admin,woju/qubes-core-admin,marmarek/qubes-core-admin