multi source backup

[omar-polo]

The current on-disk format supports multiple sources per snapshot, but the kloset interface (and so also the plakar cli) doesn't expose this feature.

[poolpOrg]

oooouh, thats nice really, so it's merging multi-root in a single tree as there's no risk of ambiguity right ?

[omar-polo]

not really, that's #58, this is for having multiple sources, i.e. plakar backup @my-s3 @my-sql @my-sftp etc...

I think these are orthogonal to each other, hence why I created two issues (and also because I needed to cross-ref #58 in a plakar issue ^^")

[brmzkw]

Side question, how would work the multi-sources restore?