In clusters a storage was pushed as many times as there are nodes
using it. Ensure we only push a path once, do this with a memory
oriented solution, i.e., build a extra object to remember what we
already pushed. This is preferred over a me.findExact call as it's a
o(n) vs o(n^2) solution compute wise and we make the user wait if
this would need long, so reducing compute time over memory use is
here a good choice - even if we will seldom run into situations where
this actually will make a difference with such small data counts.
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>