Models junits are failing locally

Models junits are failing locally

Junits were failing in my local eclipse environment.  Fixed the
following:
- more cases of "is marked @NonNull but is null" (I thought Liam had
  already fixed all of these, but I'm still seeing errors, so fixed
  some more)
- comparing "Instant" values in event time stamps assumes that
  the times will be different, but may not be, if the JVM is fast
  enough.  Modified the test to set the times of the new events to
  Instant+1, to ensure that they are different from the original

Issue-ID: POLICY-2305
Change-Id: Ic05bc6a58b559ba589583ce887711ee01f76691c
Signed-off-by: Jim Hahn <jrh3@att.com>