stitch: return result map from PackMulti.
stitch: return result map from PackMulti.

There's more info that's important to return from multiple packs than there is from a tree of unpacks: in unpacking a tree, we can basically forget about the wareIDs again because we typically only care about the whole set of filesets now manifested.  Packing is the opposite: we're done with the filesets, and its the WareID we care about after this.

Signed-off-by: Eric Myhre <2346ad27d7568ba9896f1b7da6b5991251debdf2@exultant.us>

polydawn/rio,polydawn/rio