Bug#846216: RFS: node-proper-lockfile 2.0.0

[Paolo Greppi <paolo.greppi@libpf.com>]

The repo on alioth is ready:
https://anonscm.debian.org/git/pkg-javascript/node-proper-lockfile.git

For the version dependency on node-retry >= 0.10.0, discussed here:
-
https://lists.alioth.debian.org/pipermail/pkg-javascript-devel/2016-December/016454.html
-
https://lists.alioth.debian.org/pipermail/pkg-javascript-devel/2016-December/016559.html
I have found that after relaxing it the tests still pass. So this could
be a feasible workaround while we decide what to do with node-retry.

Please someone more experienced than me review it and if it's OK sponsor
its upload.

Thanks,

Paolo