The List Images API endpoint has accepted multiple values for the
`since` and `before` filter predicates, but thanks to Go's randomizing
of map iteration order, it would pick an arbitrary image to compare
created timestamps against. In other words, the behaviour was undefined.
Change these filter predicates to have well-defined semantics: the
logical AND of all values for each of the respective predicates. As
timestamps are a totally-ordered relation, this is exactly equivalent to
applying the newest and oldest creation timestamps for the `since` and
`before` predicates, respectively.
Signed-off-by: Cory Snider <csnider@mirantis.com>
0426c76142