Maint/master/update rsync flags

Retry When Shipping
We currently fail occassionally when shipping, and it appears to be a resource
contention issue. This commit updates the ship tasks to retry a ship after
failing.

Update rsync flags
We currently use contradictory rsync flags, especially around setting and
retaining permissions. Since much of our trouble with shipping stems from
permissions settings, it doesn't seem to be worth the hassle. This commit
removes any set-permissions flags, instead explicitly avoiding setting
permissions.