deployment: use just the timestamp + a bit of random for the id
This significantly reduces the size of the id, we can do so because:
- and as we don't expect to have so many deployments per second
- deployments are already namespaced per-tool namespace
So it's unlikely that they will collide.
Depends-On: !57 (merged)
Signed-off-by: David Caro dcaro@wikimedia.org