LP#1676608: fix glitch with egCore.pcrud.apply()

LP#1676608: fix glitch with egCore.pcrud.apply()

pcrud.apply() is supposed to skip any entries in the list
of CUD actions that don't explicitly mark themselves as
being a creation, update, or deletion, but didn't manage
to fully skip them. As a consequence, the browser console
would note complaints that open-ils.pcrud.apply.$IDLCLASS
methods do not exist.

Signed-off-by: Galen Charlton <gmc@equinoxinitiative.org>